Summary

Most motorsport wiring failures don’t come from bad crimps — they come from incorrectly sized wires and misunderstood current loads. In this webinar, you’ll learn how to accurately calculate real-world current draw and choose wire and fuse sizes with confidence — no guesswork required

00:00 Hey everyone, Caleb here at High Performance Academy.
00:03 Welcome to another webinar.
00:05 A pretty important thing with wiring and electrical is our wiring itself, and something some people come stuck with occasionally is how to appropriately size our wire for the job that we're going to be wiring up.
00:18 It's very important to get this right, it can go pretty wrong.
00:22 You get things like smoke and fire and or on the good side of things just, you know, things just shutting off.
00:28 Now, today I'll try and clear up some things.
00:31 We'll go pretty deep into electricity and what is actually happening, so we can get a bit of a better understanding of why things are important to consider.
00:39 And also if you've seen one of our webinars before you might be thinking why am I, so much shorter today? Well, I've got a foot in a moon boot and I'm currently sitting down, so please don't speak about it.
00:49 Continuing on, this is a recorded webinar, so if you are not able to get to the webinar today or you need to watch it another time you can be able to jump online after it'll all be uploaded.
01:00 If you're here with us live today, welcome, thank you for rocking up and putting up with me and what I have to talk about today.
01:08 So, let's get into wiring the absolute fundamentals I guess of electricity.
01:14 It's going to help us imagine what's going on.
01:17 I find it really important to, you know, delve deep into the topic and figure out what's going on underneath everything else to get a really good idea of why we make the decisions we make, choose the components we do, rather than just going hey this is 10 amps I'm going to pick this wire, done and gone.
01:35 If we come over to our whiteboard here we've got a few quick little drawings.
01:40 People who are well into physics please ignore the inaccuracy of my drawings, you'll get annoyed, but we're just going to move on from that.
01:48 What I've got at the top here is an atom.
01:51 This is representing a copper atom.
01:54 We have a nucleus on the inside which has protons and neutrons.
02:00 The blue dots on the outside are electrons.
02:03 The fundamentals to this is a proton is a positively charged particle.
02:08 Neutrons are neutral and our electrons are negative and this is where we get our positive negative charges and things from electricity.
02:18 So, what happens is we have this bunch in the middle of the nucleus.
02:21 Our electrons are floating around and with copper in particular we have an equal number of all of them.
02:28 There's the same amount of positive protons, neutrons, and electrons and everything is sitting happily in equilibrium.
02:35 We have this one electron however on the outside.
02:38 He doesn't get involved with everyone else and he's a bit of an outsider, so sometimes it can jump out and actually leave the structure.
02:45 It's very easy for this to happen.
02:47 This is sort of the core principle behind what makes a material a good conductor is its ability to move electrons on.
02:55 Because copper has this one electron that can be knocked off and leave the structure completely, it's the reason why we use copper, so much in electrical.
03:06 It's, I wouldn't say cheap, but as far as other alternatives it's a cheaper option, but still a really good conductor.
03:13 Better options would be things like gold and silver, obviously more expensive, but they have the same idea where they can pass on their electrons a lot easier.
03:23 So, what happens here is we say this electron just leaves, heads on out, we've got then what happens is we have a hole there.
03:33 And because that electron was negatively charged we now have less negative particles than the positive protons.
03:41 And we would then say that this atom is now positively charged because it has more than the negative electrons.
03:50 I'm going to be saying these words a lot, so hopefully I won't keep stumbling over it.
03:54 What this means is like magnets opposite charges will attract each other, like opposite poles of a magnet, the positive is attracted to a negative north-south.
04:06 So, another electron that's floating around which is in itself negatively charged, we attract it to this hole because this atom is positively charged.
04:17 So, what this basically means in our copper wire which I have down here, that's imagine inside the copper wire these red dots are our electrons, sorry not electrons, they're our atoms.
04:31 And amongst this we have the occasional electron which is just floating around because it's left its atom and it's gone bouncing about.
04:38 When the wire is just sitting there stationary it is still in equilibrium and basically that just means electrons, they're moving about, but they're doing it every which way, there's no sort of one direction in particular and it's still in this equilibrium where nothing is moving in any particular way.
04:56 It's all just sort of free floating.
04:59 But what this means is these electrons, what I want you to take from this is that there are electrons moving around copper and the way its atoms are built allow for these electrons to move quite freely.
05:12 Now, if we look here we have a battery, I'm just going to go drinks, I am parched.
05:17 So, in a battery it's using similar principles, well pretty much exactly the same, we are using a chemical reaction inside the battery here and what that's doing is pushing a heap of those negatively charged electrons down to the negative pole of our battery.
05:36 And that's what makes our negative side of the battery a negative side because there is a whole bunch of these electrons and they, when I said before that opposite charges attract each other, the opposite like charges want to repel each other.
05:52 So, all these electrons that are negatively charged bottom of our battery, they really try to push each other away and get out.
05:58 On the other side of the battery we have an area where there is just positively charged and there's holes from these atoms that don't have electrons and ideally these electrons want to get back to there, but there's stuff happening in the middle which stops that from happening.
06:12 That's the core principle we're doing on a battery and what we have then is potential and you might hear people say there's a voltage potential or a charge potential and that's exactly what we're describing with voltage.
06:25 In this battery we, in a double A or something you'd have one or two, but because of cars we're going to say 12 volts.
06:31 So, we have the potential for 12 volts to pass through a circuit and that's because of how many electrons and the setup of the battery.
06:41 So, we have this potential here ready to do something, it's ready to do work.
06:44 It wants to move and go somewhere, but at the moment it can't and that's the same as if you put your multimeter across a battery, that's what you're reading.
06:51 You're just saying that there's the potential for voltage to move across, there's that 12 volt.
07:00 So, in that, I'm just looking at my notes quickly, so I'll make sure I'm not forgetting anything.
07:07 So, in that we want to give it somewhere to go, we want to make these electrons do some work.
07:13 So, we're going to take our copper wire and I know this is probably frowned upon, but we're just going to short it out, we're going to go from the negative to the positive.
07:22 And because we've got these electrons moving around, there's holes and things, these electrons here that are really trying to bust out and get somewhere, they're going to start filling those gaps and pushing electrons out the way.
07:33 They're going to start filling it up and it's going to move all these electrons down across the wire and eventually these ones that are the positive side are going to go back into the battery and start filling up there.
07:43 When that happens the chemical reaction continues to process, those move down to the bottom, that's how we continue making a charge.
07:55 Now, this is all going to be important eventually with working out wiring sizes and stuff, I'm trying to...
08:00 I really want to delve deep into what is actually going on on the atomic level so we can kind of understand that.
08:06 So, these electrons are now able to move and they do.
08:10 If you look at it really really quick there is a kind of a wave that goes around, but we think of it as it's just a constant sort of thing happening, it's like it's all moving as one, it's not, so much, you know, there's one head racing along, it's the whole process is moving together in one sort of fluid motion.
08:28 And what do I want to get to next? One thing you're probably going to notice is I've been talking about electrons going from negative to positive.
08:36 This might be confusing sometimes if, you know, everywhere you talk about electricity when people talk about it they talk about power flowing from the positive to the negative.
08:46 This is because a long time ago Benjamin Franklin decided, or he didn't decide, he guessed that that was what was going on, that charges were moving from positive to negative.
08:58 Everything was sort of written around that and decided that that was what was happening until someone actually proved that no, it actually goes negative to positive.
09:05 Unfortunately, I've completely forgotten and didn't write down who that was, props to them.
09:09 So, you often always hear about talking about going from positive to negative.
09:13 When we're talking about on the actual atomic level and we want to talk about our electrons we need to talk negative to positive.
09:21 And when it comes to making calculations for your amps, resistance and all that, these calculations aren't affected by this and that's why it doesn't actually really matter at the end of the day.
09:30 It's more helping for visualizing and knowing what's going on.
09:34 Okay, so we've got all these electrons that can now move around.
09:38 We want to make them do some work.
09:40 Now, when we make things do work, probably the best example is a light bulb.
09:46 We want a filament inside the light bulb to glow and we do that by heating it up.
09:51 And the best way to do that, we do with electricity, we pass electrons through a resistive wire.
09:58 So, what's going on, we'll cut this out here, we install a resistive wire and basically just this bit here is a different material than our copper.
10:12 For most filaments I'm pretty sure they just use tungsten because it can withstand very high heat.
10:19 That tungsten is actually very restrictive.
10:24 The structure of the atoms and things don't let the electrons pass through nice and freely.
10:29 They do pass through, but they have a lot of work to do to get through that.
10:33 And the key there is I've they have to do work to get through.
10:37 So, basically what happens is our electrons, as they come through this section, they start hitting atoms and they start bouncing off, going bang bang bang, pinballing and atoms start to vibrate and that is then what eventually creates heat.
10:52 They vibrate to the point where that filament gets, so hot that then it starts to glow and emit light.
10:59 So, we've turned the kinetic motion energy of our electrons flowing through a wire, we've forced them through a section with a material that makes it hard for them to do it and they have to do work, that creates heat and creates our light.
11:15 And that is how a light bulb works from electricity.
11:18 I'll also add that we use tungsten inside of a sealed glass bulb because if you had that in just open air the tungsten would just burn up and it would melt essentially and cut our circuit.
11:31 The bulb is under vacuum which removes air and stops it from actually burning.
11:36 So, that's why when you throw a light bulb at the ground it makes that nice pop sound and we all get satisfied.
11:41 Anyway, so that is how we create something from our electrons moving.
11:48 Now, when that's happening obviously, well maybe not obviously, energy can't be created from nothing.
11:55 We are just moving it from different states and we're using other ways to move it through our wire, out through energy and things like that.
12:06 In our battery we're using a chemical reaction that is producing energy by pushing our electrons out, that's then passing through and when it gets to our light bulb we're converting that motion, that energy, into heat and light and we are losing some of it because that goes out into the wilderness.
12:25 We have our light energy and we all know when you stare into a light bulb you get blinded, you touch it, it's nice and hot, that's all that energy escaping.
12:35 And that's why we eventually end up with a flat battery because those electrons don't have enough energy when they get back, they lose that energy at the light bulb.
12:45 And that we can actually see by a voltage drop which is something really important and probably the main thing I'm trying to get from this is we need to take into account voltage drop when we're sizing our wires because as I said this light bulb has a very high resistance, that's what's creating our heat and our electrons doing work.
13:09 Our section of wire here, from here to the light bulb, is going to have its own resistance.
13:15 Everything has some sort of level of resistance.
13:18 We choose copper because it has a very low resistance, electrons can flow through, but at the end of the day there is some resistance there.
13:26 And this is important because the longer the wire is the more this resistance increases and that becomes very important when we're sizing our wire as I'll get to a bit later.
13:36 Before that though I'll talk about how we sort of reference all this.
13:41 We always hear about amps when we're talking about electricity especially in cars and what amps are or amperes, basically it's a way of describing how many of these electrons are moving through a point at a certain time.
13:58 Now, as I've pointed out we've been talking on atomic level electrons are incredibly small, they're unfathomably small, you're not going to ever see them.
14:08 There's, so many packed into a small space that to calculate, if you wanted to calculate how many were actually moving in a space, the numbers would just be dumb and annoying to try and calculate.
14:20 So, what we have then is we have a word, it is a coulomb, which is a fun word to say.
14:29 Basically, a coulomb is just a big group of electrons.
14:33 We use it, we say one coulomb, what that is equal to is 6.242 to the power of 10 by 18.
14:49 That is a huge number, that is a lot of electrons.
14:54 It is, what's the number, it's quintillion.
14:58 It's a 6.242 quintillion which is, what is it, million million or billion billion I think.
15:06 I'm actually going to look that up because it is important.
15:08 It's billion billion, it's 6.242 billion billion electrons.
15:13 And just because it's fun to write out we're going to go 6.242, then we have 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18.
15:40 That is how many electrons there are in one coulomb.
15:45 One amp equals one coulomb, one coulomb per second sorry I should say.
15:49 So, that is why we are using the coulomb number because rather than saying 6.242 quintillion electrons are passing through here per second we can simply say one coulomb per second.
16:05 And that is what an amp is.
16:08 I'll just write that down quickly.
16:12 One amp, which we often use a to refer to, equals one coulomb.
16:19 And that's, sorry, one coulomb per second.
16:25 And to sort of get your head around that, if you think about speed, speed is, we measure that with distance traveled over time.
16:38 So, this is essentially the same thing.
16:41 We're using amps as our speed description whereas this would be maybe kilometers per hour, miles per hour.
16:47 We're using the word amp or ampers.
16:50 And that is our amount of coulombs or our giant number of electrons.
16:57 That are moving per second.
17:00 So, that's when we're saying that there is an amp, excuse me, when we say that there are one amp or two amp, it's the amount of electrons that are flowing past this point in a certain time.
17:13 So, hopefully that gives you a bit of an idea of electrons.
17:17 Also a good way to describe this is with electricity a lot of people you'll always hear it referred to using the water analogy.
17:27 If you think about one that I like, you have a tank and that tank is full of water.
17:36 And if you put an outlet down the bottom, because of gravity, the weight of that water, with it closed, basically it wants to come out of that outlet.
17:46 There is a potential for water pressure to come out of there.
17:49 So, it wants to push out.
17:50 So, that's our voltage.
17:51 We have a battery with electrons that want to push it out and get out of our battery.
17:56 We add a hose to this, comes down, there's an outlet, we get water, then that starts flowing through here.
18:04 And we usually refer to that as liters per minute or gallons per minute or whatever the Americans say.
18:10 And, so that's the same sort of thing as our coulombs per second.
18:15 Now, we might have five liters passing through per second, whereas here we have two coulombs per second or two amps.
18:23 Now, when I talked about restriction, the resistance of this globe, with the water analogy, essentially what we're doing is pinching that hose off and now that water has to do more work to get through and it creates more pressure.
18:39 So, that is our current doing work through resistance.
18:45 Voltage is our stored energy, current is the flow of our electrons or water, and resistance is the force stopping it.
18:56 It's resistance in the line.
18:59 Now, all of these things that I'm saying are voltage, resistance, amps, they all come together as well.
19:06 I think I've got plenty of room here.
19:08 What you'll hear a lot is Ohm's law.
19:11 Ohm's law is, the best way I've seen it is there's a triangle and we have voltage.
19:19 I is used to, it's the mathematical symbol for current amps and then resistance.
19:28 Resistance you'll always hear it referred to in ohms, milliohms, kilohms.
19:34 Sorry guys we lost you there, had some technical difficulties.
19:38 Let's jump straight back into it.
19:40 Hopefully, the last thing, I'll just quickly go over that last little bit.
19:44 I was talking about amps, coulombs per second.
19:47 I apparently couldn't see that as well where my screen is.
19:50 And then I was talking about voltage, current and resistance, Ohm's law and how it all works together.
19:58 So, another one I'll just quickly say before we get too deep into that.
20:02 The power being emitted by say a light bulb, the energy that we're losing in heat and light, we use power to describe that or watts.
20:13 So, a common light bulb for a taillight is rated at 21 watts.
20:20 So, that means there's 21 watts of energy that comes out of that.
20:25 And that also works into, there's another triangle, there's charts that will give you all this in one, but this is just the one I've always known.
20:36 Yes, that's right.
20:38 It basically just swaps the... no, that's not right.
20:44 The V, of course it's gonna smudge.
20:47 V, V, voltage, current, resistance, power, current, voltage, U, V.
20:55 Okay, so what does that mean? We can use, as long as we have two of these components, we are able to calculate the third.
21:02 And that comes really handy when we're trying to do things in here.
21:05 And basically the way we do that is if we look at this, if we want to find our current, so say we want to find out how many amps is going to pass through a component, we know the resistance and we know the amps, we can use current, which if we look at this, I will equal voltage over resistance.
21:26 So, basically this means we take our voltage, which might be 12 volt, and say there's 6 ohms of resistance, then it's 12 over 6, 12 divided by 6 is 2, so there are two amps, I equals 2.
21:40 And that's how we use that to calculate things like that.
21:43 I won't go too deep into it, just it is on our course, we get into that a bit more, that's sort of the core principles behind electrical and automotive electrical, but we do need to understand that for calculating our wire size and knowing what's going on.
21:59 I just want to take a quick note, if you have any questions, chuck them into the chat, talk to the guys there, they'll get that to me, and at the end I'll try and answer any more questions.
22:09 Hopefully, there's probably going to be a few on this, or I've just completely said it all as it should and it makes sense, so hopefully it does, otherwise I will get to those questions at the end.
22:19 So, why does this matter for us choosing our wire size? Like I said, voltage drop is a big thing.
22:27 This wire here has resistance, and the voltage drop from that wire can really affect things that are in line that we want to power.
22:39 The whole light bulb is actually a really good example, because if we have a voltage drop and say by the time it gets here we're down to 10 volts, 9 volts, 8 volts, extreme situation, that light bulb can't emit as much energy as we want and it will be dull, which is not what we want.
22:57 So, ideally we want the maximum amount of voltage there, so I'll eventually show you how we're going to calculate that and how it's actually going to become important in our wire sizing.
23:08 And, so we can use here as well, I can actually tell you the resistance of this light bulb based on this, so if we take our second one here for our second triangle, which has our power in it, we can take power which is 21 and that's going to be over the other part that we know which is our voltage, 12 volts, and from that we can get our current.
23:30 Now, I'm just going to jump on a calculator here, you don't need to watch, I just don't want to do it in my head otherwise I'll make a fool of myself.
23:37 1.75, so 1.75 amps.
23:43 So, from that we know now this light bulb is drawing 1.75 amps of current.
23:51 From that we can also now get the resistance because we have two of our components in here.
23:56 So, we have our 12 volt which is going to be over our current which is 1.75.
24:04 My terrible writing here, apologies.
24:06 And, so our resistance is going to equal 12 divided by 1.75 and we get a resistance of around 6.86 ohms.
24:19 Oh my god, sorry.
24:22 Yeah, this is a symbol for ohms.
24:27 Now, in this situation, you know, it doesn't mean much to us right now.
24:30 We'll still wire it up as is, but I'm just trying to show you how all this sort of works together.
24:37 What is important is the resistance of this bit of wire here as I keep saying over and over again.
24:47 Before I do that, we'll just... what was the point that I already want to make? It's the energy that you're losing here, the voltage drop across our component.
24:56 When we have just one thing in our circuit, a light bulb, our voltage drop across there is going to be our 12 volts.
25:04 We're going to lose... we're going to have a full voltage drop across that one component because when we measure across here from this point to this point, we're essentially measuring positive, negative and of the battery and you'll see that voltage.
25:17 It will be slightly lower than the battery ourself and that is because of our voltage drop across the wires, but we'll get more into that later.
25:24 I keep getting digressed and distracted.
25:28 But just as a point, yeah, there is a loss across the components that are in there and that is also why we don't wire things in series, particularly with things like light bulbs.
25:39 If we were to go over here and put another light bulb in, basically we get voltage drop from this light bulb and then we have... that's then not leaving enough for that light bulb and it will be dull.
25:51 That's why we wire things in parallel because what electricity does is it splits off and it goes evenly across the... well, just kind of evenly depending on the resistance either way.
26:03 Electricity wants to go in the path of least resistance which is something you've probably heard a lot.
26:07 Sorry for the squeaking in my chair.
26:10 Let's sort of get away from this now and we'll start getting into actual wire and wiring things so, I can stop boring everyone.
26:18 I've probably missed something.
26:19 Chuck it in the chat if you want me to explain something a bit further or if I've just butchered something and you're a physics guy and you're like the hell is he on about? Wiring.
26:29 Now, if we jump over to the macro camera real quick, I've got a couple of wires sitting here.
26:37 Now, over here we've got this one on this side is a... it's a PVC coated just sort of everyday automotive wire that you can get from pretty much any automotive shop.
26:48 And on the other side here we have our Tefzel.
26:52 It's the wire that we use in the motorsport industry with pretty much everything.
26:58 It's the 2275932 wire and you can straight away see some really big differences.
27:06 Now, these two wires they actually have very very similar conductor sizes.
27:12 So, the PVC...
27:13 I'm just looking at my computer... if we show the computer here I'll show you this is from the catalog for that wire.
27:22 In our cross section of the conductor it says we have 0.64 millimeters squared.
27:28 So, that is the base of the surface area if we cut it lengthwise, cut it along the width of the actual conductor inside, not including the insulation.
27:38 I've also got here...
27:41 Yep, so this is for our 22759 Tefzel wire.
27:46 If we go by 20 gauge wire it is 0.62 millimeters squared.
27:50 So, these are very very similar in conductor size, but you can see on the macro that they are...
27:57 The insulation on them, the coating is drastically different.
28:02 If we look on the chart for the...
28:05 It's referred to as 2.5 mil, that isn't actually the size it's just the base of the name used for the 0.64 millimeter squared conductor wire size.
28:17 They have it listed as 5 amps.
28:19 Now, this is probably where people come unstuck a lot, they just look at these numbers and they say okay it can handle 5 amps, I'm going to run 5 amps through it or whatever.
28:27 This can really get people into trouble and I'll talk about that why and our voltage drop is one of the key things in that.
28:35 But for this wire in particular, so we can see here it says 5 amp, so you know we'd think going back over to our Tefzel it's the same conductor, surely it's rated at the same power.
28:49 But if I go over here that's the same chart, all right up here I've got a Tefzel chart that actually, says our 20 gauge is rated at 10 amp.
29:00 So, there's a huge difference here, but we've got the same conductor size.
29:04 So, this is where things can get confusing.
29:06 You'd think you'd be able to handle the same thing.
29:09 Now, these charts that are all over the internet and you can find everywhere, the thing with these is they're based on very specific situations.
29:19 From memory this chart is based on allowing a 30 degree increase in temperature, it's based on a certain voltage and everything, I don't have the information here.
29:32 But the key thing is it should only be used as a kind of a ballpark or a guidance because the situation that these numbers were made and the wire was tested at won't be the same as a situation in your car.
29:47 And there's lots of things that influence how the wire is going to react and how much heat we're going to get out of that because at the end of the day one of our biggest issues with wiring is heat.
29:59 And it's got to do with our, as I was showing you, the resistance in wire as those electrons are passing through, it creates heat.
30:06 And because we have resistance in cable itself, in the Tefzel wire, that is going to generate some heat.
30:13 So, how do we get this 10 amp or 5 amp rating and why is it, so drastically different when we've got the same conductor size? The key here is the coating.
30:25 The PVC, which is quite thicker, actually has a much lower tolerance for heat.
30:31 If I go onto the page here, they say here it's a polyvinyl chloride which they have as V90 PVC.
30:41 And the key thing here is 90.
30:42 90 is actually the temperature that it's rated to.
30:46 So, 90 degrees, that insulation will actually start degrading and causing issues.
30:52 Our Tefzel on the other hand, I think I've got to I guess the biggest important thing here is the size difference too.
31:05 We are achieving a much higher temperature range from a much smaller coating which just is better for us in general.
31:13 We can fit more wires in a smaller area without worrying too much about how that heat is going to affect our coating.
31:20 I'll give you a good example of how heat is going to mess things up, but I just want to make that clear for the different types here.
31:27 And just quickly, if you've looked into milspec wiring, the 22759 spec wiring, you'll notice a lot of the time, specifically the ones I've seen, you'll see the slash 16 or slash 32.
31:40 These are slightly different coatings, but still very much, they're both considered Tefzel.
31:46 Our 16 is now Tefzel, it's a polymer and it is it's written here somewhere, here we go, ethylene, tetrafluoroethylene, ETFE, that's what the coating is.
32:01 And our 32 series wire is a cross-linked version of that, hence the XLB4 cross-link ETFE.
32:10 It's slightly better with abrasion, it's slightly smaller, but as far as both of those, Tefzel and XL, ETFE, 16 and 32, they have the same temperature range.
32:23 So, we'll stick to the 32 when I'm referencing now because that's what I've got the chart here for and that's pretty commonly the one that we use in Motorsport.
32:32 It does say here, this is actually a really good site, if you can see the website here, I recommend looking it up, there's some really good literature in here.
32:41 I think it is referenced on the courses at some point.
32:45 The key thing I want to take from this is our temperature range and now I'm going to take these wires and I'll grab, without falling off the chair, my heat gun, so we can do a fun science experiment.
32:57 You may have seen Andre do this before, sorry for the loud noises, let's crank the heat up, get our two wires and we're just gonna blast them with a bit of heat.
33:14 I'll try and keep it fairly even, wait for the heat gun to heat up.
33:23 Now, already I'm seeing the PVC react, it's swelling up, you can see it's starting to melt and I mean that's only a few seconds, but that's giving us a result that you can actually see.
33:37 So, I set it at the same temperature, let's get this in a position we can actually see.
33:43 Let me just bend that.
33:47 So, really the Tefzel doesn't even look like it's been touched, it still looks beautiful, but we look, at our PVC and that is just a mess.
33:56 The PVC has obviously not been able to withstand the heat, it started degrading and it's melting, that becomes a real issue when we have multiple of these wires together.
34:05 Those wires can melt together, you'll often see when people have the PVC, something's pushed too many amps through, too high a temperature, those wires have actually melted together and from there short-circuited, maybe a power to a ground and that's just all in all a big issue.
34:24 So, how do we stop that from happening and how do we make sure that doesn't happen with our Tefzel? Well, it comes down, like I said we use these charts as a reference point to start off with.
34:36 So, I'll go back to our list here and this chart that I've got, so when it says 10 amp it's saying that we can put more amps through and generate more heat in that wire because the coating can handle it, it can dissipate that heat nicely, excuse me, but that PVC is only rated at 5 amps because even with the same size conductor it can't handle the heat.
35:02 So putting, if you were to put 10 amps through it, it would start melting that conductor because the electrons moving through the resistance of that size wire is going to start creating too much heat and your PVC breaks down and causes issues.
35:16 Our Tefzel on the other hand can handle a higher temperature, it can handle those electrons moving about and shuffling around and causing heat, so they rate it to 10 amps.
35:26 So, this gives us a good starting point, we can say we want a wire that can handle up to 10 amps, but we need to look at the resistance of this wire and our voltage drop.
35:38 I will probably... is there anything I've missed in far as wiring? Another wire is TXL, it's much better than the PVC on par, or a little bit less than the Tefzel, it's another wire you'll often hear used and referenced in motorsport wiring.
35:55 I'm just using the Tefzel and PVC as a drastic difference.
36:00 Some of the things people really forget to consider when they are choosing their wires are things like how the wiring is bundled.
36:07 As I said, the PVC sitting together closely together, they can melt together, it also affects how the wire can dissipate heat.
36:15 It's the same as trying to keep each other warm when it's really cold at night and you and your buddies are just... the heat is broken, you get really close and your body heat is transferring between each other.
36:28 The wires are doing the same thing, they are, so close to each other they're transferring heat into each other and affecting the total heat that is there and it can't dissipate into the environment.
36:37 So, we need to really consider, is our wire bundled in a big bundle like this in front of us, concentric built, and there's lots of wires together.
36:46 Lots of these may be having current passing through and individually there might be small amounts of current and causing a small amount of resistance and heat, but built together it can build up quite significantly.
37:01 So, we need to think about that.
37:02 We also need to think about environmental heat, so external heat, things like engines, our exhaust is probably our main heat source coming off the engine when we're trying to wire around things, but even just smaller things, your radiator, coolant pipes, your heater under your dash, all these things radiate their own bit of heat and that can soak into our wire and cause it to add on to the temperature that it is already producing.
37:32 The way they describe it in these situations when they rate it to 10 amps, they basically say they're allowing for 30 degrees rise above ambient.
37:46 So, if ambient temperature is say 60 degrees in the engine bay of the car somewhere in the corner maybe, that wire will heat up another 30 degrees on top up to our 90 and it's still going to be okay based on what they've calculated.
38:01 We'll see as we saw with our PVC, that's only rated to 90 degrees in that situation it wouldn't be okay and it would actually start melting.
38:08 And, so that's one of the things they take into consideration when calculating these working current.
38:15 The other thing which I keep saying over and over again is the voltage drop and that is based on the length of wire.
38:22 As I said, as we extend the wire we are introducing more and more resistance because we have more and more material, more atoms for it to bounce around.
38:31 So, the longer that a piece of wire is, the more voltage drop we're going to have, more resistance it's going to have, and the more heat it's going generate as a whole.
38:41 So, that's why we need to consider the length of it.
38:44 And then there's just the general things like what voltage we have, some components we may need to only consider running at 12 volt, whereas others we'll need to think about running at charging voltage 13.5, 14 volts.
38:57 So, there are other things that need to be taken into consideration and then also the actual current draw or power of the component.
39:07 So, I'll try and now we'll actually get into or pick a component.
39:11 If we look on the computer here I've got the SPAO website.
39:18 So, let's think we've got a fan.
39:21 I've picked a very small fan, say for an oil cooler we might want to chuck down in the front passenger side fender of our car to cool down our engine oil cooler.
39:33 Selected it here, it starts at the top, it gives us a nice chart for airflow and it also gives us a good current draw reference.
39:40 So, these are the things we need to know when it comes to wiring our components, what current draw is going to be drawn by those components.
39:49 And another sort of, I guess, misconception is components will only ever draw what they need.
39:57 The component itself isn't going to just start drawing stupid current for no reason.
40:01 If it does it's probably a short circuit inside, an issue, but at the end of the day at a specified voltage it will draw 7 amps as this chart is saying and that's not going to change unless you change one or the other in our ohm's law voltage or resistance.
40:19 So, looking at this chart we can see the pressure, no pressure, it's got its highest flow we get 7 amps and as the airflow decreases there's more pressure, it's struggling to move air, it increases the amps which is a very common thing with motors, DC motors such as fans, fuel pumps, that sort of thing.
40:41 When they have to work harder they're going to draw more current.
40:44 So, from this we will say we want to take a worst case scenario, we're trying to prevent the horror happening of wire burning and that sort of thing.
40:55 So, we want a worst case scenario.
40:58 So, going by this 8.2 amps, I'm going to write this down here just, so we can sort of get away from all the different numbers.
41:04 We have our fan, I'm sorry if we have to jump back and forth, fan is going to be maximum amps of 8.2.
41:13 Now, we want to leave some headroom and we do that by adding a derating multiplier.
41:23 So, I'm going to add another 20% onto that.
41:26 And if I do 8.2 times 1.2 we get 9.84.
41:32 We're just going to round that up to 10 amps just for an easy number.
41:37 So, we're going to say in our worst case scenario with, I wouldn't say an issue, no things like short circuit, just a bad day for the fan, it's struggling, but it's in its normal working conditions, we might get up to 10 amps of current.
41:53 And, so going by our diagrams that I had before, what that's saying is our fan is going to have a high resistance because it's working, so hard and the electron is trying to push through there or...
42:08 Now, this will be at 12 amps, yep they specify here 12 or 24 for other fans.
42:13 So, at 12 amps when the resistance is high it's going to draw 10 amps.
42:17 So, that's our first thing we're going to take into consideration.
42:20 Now, a lot of people might just go with that and then go back to our chart here on the computer and say hey 20 gauge wire that's rated at 10 amp, let's go we'll wire it up with the 20 gauge.
42:32 We've still got our headroom there because we derated it.
42:35 But the problem is we need to take into consideration all our other environmental and heat considerations and especially our voltage drop which I promise I'll get to in a second.
42:50 With our wiring we might be running it past, because it's on the radiator, we might be running it past some hot coolant hoses and that sort of thing.
42:59 So, not just with the wire size, we need to think about how we're going to we can avoid it, run around or heat protect it, but in a situation where it has to go there we need to think about okay, this is going to have more heat.
43:14 So, what more heat does is it excites those atoms more and makes it even harder for the electrons to pass through.
43:20 So, adding external heat into the wire is going to actually be worse for those electrons and there's a very good chance that there's going to be more than that 10 amps going through the wire because of those external heat influencing it.
43:35 So, taking that consideration we might think okay 10 amp, 20 gauge might not actually be the best situation, but a good way to actually check and this is where things are getting important, is our voltage drop.
43:47 So, we've got our battery, I'm going to go back to a car style battery, what am I doing here, positive, negative, and we're going to have our fan.
43:56 And I'm going to draw this really good because that is a fan and we're going to hook it up negative and positive.
44:06 Now, we're going to think in conventional here our current is going from positive to negative, we'll continue in that way just to make it a bit easier.
44:16 We're going to think about the voltage drop from our positive to the fan itself.
44:23 So, how do we do that? We need to know how long this wire is.
44:27 We're going from, we're going to go from the fuse box under the dash say, it's going to travel you know maybe go along the dash down the fender and then back around to the radiator.
44:40 We might end up with we'll just say three meters maximum length there.
44:44 Sorry for all the guys that work in feet and you know toenails, that sort of thing, but I need to work in this for this sake.
44:53 What we do now, we know the length of that wire, three meters.
44:57 What else we know is our voltage.
45:00 Write that down.
45:01 We're going to, because our fan's going to run during while our engine's running, it's generally, going to run at 13.5 volts.
45:09 We'll just give or take depending on how good your alternator is.
45:12 So, we know our length, we know our voltage and we also know that our worst case scenario 10 amp current draw.
45:26 So, we've got a heap of things now we can put into our voltage, our ohms law.
45:31 I'll just check that back up here.
45:33 Voltage, current by resistance.
45:37 And we want to know our voltage drop across here.
45:40 And that is in these charts as well.
45:42 If we have a look on the computer, I've got this chart on the bottom.
45:45 I ignore that arrow by the way, that was just on the image that I grabbed.
45:49 We look here for our 20 gauge wire.
45:52 We can see our conductor size here, 0.62 milli squared.
45:57 It's got here conductor resistance.
45:59 So, we can actually get the information of how much resistance our wire has.
46:03 In this case is giving us ohm by kilofoot and ohm by kilometer.
46:08 That's drastically more than what we need, but simplicity, you can just look at this as 32.4 milliohms per meter because we divide by a thousand for kilometers to meters and you can do that for amps as well.
46:25 So, looking at this, our wiring has a resistance of 32.4 milliohms per meter.
46:33 So, that's a quick equation we can do here.
46:35 We've got our per meter 32.4 and we've got our distance, 3 meters.
46:43 And because I'm not going to do a quick math on here again and make it fool myself, we do 32.4 times 3, 97.2.
46:53 Sorry, I need to convert that to...
46:55 We're back again, sorry, more technical difficulties.
46:59 Hopefully, that won't happen again if it does, bear with us.
47:02 Hopefully, it wasn't the internet getting annoyed with my bad math.
47:07 Anyway, where we left off before I was working out our voltage drop across this wire.
47:13 I got the resistance of the conductor off this graph.
47:18 Now, as I was writing down, I wrote 32.4, that is for our ohms per kilometer.
47:23 We want milliohms, so in ohms that is 0.032.
47:30 Come on Caleb, write better.
47:32 324, 0.0324 ohms per meter.
47:38 So, let's calculate that now.
47:41 0.0324 times 3, we end up with 0.0972 ohms.
47:53 So, what's that saying is in this bit of wire we have 0.0972 ohms of resistance.
48:04 Doesn't seem like much, but the problem that we come into is what we want to do then is work out the voltage drop, which we use our ohms law up here.
48:16 We have our ohms, we have the current, and we can now work that out by taking... we want to find our voltage, so V, and voltage is going to be current times resistance, so equals our current which is 10 amp times our resistance of 0.0972, which we can just move a decimal place across.
48:41 So, with this we have voltage of 0.972 volts.
48:46 And now that's almost a volt already that we are going to lose from here to here.
48:52 So, what that's saying is if we were to measure from our ground point as a reference and measure our voltage at this point just before the fan, because of the resistance in that wire we're already going to be down to... we're going to be down to 12, oh sorry, yeah 12.455 something or other volts.
49:12 So, already we're starting to drop voltage.
49:14 Now, when we're calculating there's no real set number I guess as to what voltage drop you want, but we try and keep under about 5% of our total voltage.
49:26 Under 2% is amazing and that's going to be like your ideal goal.
49:30 But if we look at this we had our voltage of 13 .5, if we divide that by our 0.972 and divide that by our voltage, and I've just stuffed up the calculator, 0.972 divided by 13.5, that is 7 % of our total voltage.
49:52 So, we're over our 5%.
49:54 This isn't ideal, we're losing too much voltage before we even get to the fan.
49:59 And, so going by just that alone, not worrying about external temperatures and that sort of thing, I'm going to say straight up that we said the 20 gauge rated at 10 amps is not going to be ideal for wiring this fan.
50:14 And that's because we are going to have voltage drop, our voltage at the fan is going to drop and cause issues with the running.
50:21 If this was a fuel pump we wouldn't have the flow that we were wanting to expect and that's the kind of issues that we're going to run into.
50:28 Going by that then, the simplest thing is we're going to jump up a size to our 18 gauge, that's rated at 13 amps.
50:37 So, even just going by that, 13 amps, even with our derated current, we've got the extra 1.8 amps, it's going to be well under that, it was going to be enough under that 13 amps that we got some more headroom and temperature-wise our coating, the Tefzel, is going to probably have a great day.
50:59 Let's do the task of calculating our voltage drop and I'm just going to do it on the side here.
51:05 So, same thing, I'll go to our chart here.
51:09 For our 18 gauge we have more conductor cross area, it's a larger, it's 0.96 millimeters squared.
51:17 So, we've got more room here for electrons to move and there's going to be a lot less resistance and that is our key thing with jumping up a size wire when it comes to voltage drop, we want less resistance for our electrons to move.
51:30 And we can see here that our 18 gauge has 20.4 ohms per kilometer or 20, yeah 20.4 milliohms, yeah that's the way, per meter.
51:45 So, we can substitute these numbers into here now and we'll just rewrite it completely.
51:50 So, we're going to have 0.0204 by 3 and straight off the bat you know we can see we've got less current, less resistance in our wire per meter and that should already make things better for us, but we want to actually calculate that and work it out for good.
52:11 So, let me do the math off screen because i'm actually just doing it in my head and we end up with 0.0612.
52:22 Straight up we're a few hundred milliohms under what we actually, sorry not hundred, 61 milliohms and 97 milliohms, I shouldn't have that extra number there it's causing me issues, but we've got a considerably less resistance in that three meters of wire.
52:40 Going by that we're going to have our same amperage, we want to find our voltage drop so we've got our 10 amps and we're going to times that by our 0.0612, 61.2 milliamps or 0.0612 milliohms sorry and 0.0612 ohms.
53:01 I really do apologize for mucking that up, so many times and what we're going to end up with then, if i can just go times 10 we just move the decimal point, our voltage drop is going to be 0 .612 volts.
53:16 Way under our 0.9 we're more closer to half a volt rather than a whole volt and if we then calculate that, divide that by our 13.5 volts it's down to now 4.5 percent.
53:31 So, we're under our voltage drop threshold, we've got our under five percent, so ideally that is going to be a good wire to use.
53:42 We can confidently say hey i'm going to use 18 gauge wire to wire from this position to our fan because we've calculated the length of the wire, the resistance, we're not going to have any voltage drop, the wire that we've chosen can withstand the current flowing through, the heat that might be generated in the heat that will be generated in that wire because the resistance isn't going to affect our coating.
54:05 If we were to use pvc coated there's a very good chance it's probably going to melt and that's where we've gone for the tefzel and we'd have to have a much larger wire.
54:12 So, we also then, we do need to consider things like the bundling and the external temperature but i do find if we got our voltage drop within that five degrees you'd have to be really you know running it by something incredibly hot and bundling up quite a bit to cause that to be a significant thing to weigh up.
54:34 I like to, i think once you've got that voltage drop within spec, ideally you want to get to that two percent, but it's not the biggest deal you're going to have still a good time.
54:46 I would say maybe something like a fuel pump something where it's critical having that voltage at a certain point right at the component itself is when you want to get under that two percent and i'll go into that a bit more after.
54:58 Before then if you got any questions chuck them in because i will hopefully have enough time.
55:05 Yeah we've got plenty of time still.
55:07 Oh there's heaps of questions already, cool.
55:09 Anyway let's continue.
55:11 So, that's yeah we're using now our voltage drop to calculate what our wire size and of course on our negative side we do need to consider that as well.
55:21 A lot of the time in our automotive situation we're going to go to a chassis earth or like the engine earth which there's very little resistance as far as you know what's happening between there and we only really need to think about that sort of small section that's not long enough that it's going to actually you know cause us big issues and we're also not wiring anything in after that component, so voltage drop after the fan isn't a big deal we're more worried about if it's going to be able to carry the amps because our amps 10 amp in our circuit goes all the way around no matter what it doesn't sort of slow down at some point or increase or decrease if there's a component in that circuit drawing 10 amps that's what we're going to draw.
56:04 So, where we do need to sort of consider though is if we had say two fans here and then we tied both of them together into a single wire we need to consider the current draw of both components into that one wire.
56:22 So, with current what you do when they're wide and parallel like this your current simply just adds together if you have two of the same fans each of them at 10 amp you're going to have a total of 20 amps when they're combined together.
56:34 So, we would then need to go back and redo these calculations look at the different specs and this section of wire will need to be able to withstand that 20 amp and it's going to have 20 amp going through, so we would substitute that 20 amps into these numbers effectively as you can see here if we stuck with the 20 gauge we would be well up to 1.8 volts in voltage drop and that would not be ideal at all.
56:58 Let me just have a quick look through here if i've gone over anything too drastic no i think hopefully, that's given a good idea a bit more of an idea of how we actually rate our wiring it's you know it's not, so much just grabbing one of these charts and saying hey this says 10 amp it's good for 10 amp i'm just going to run 10 amp through it or a little bit less it really does matter how long your wire is you know that's a huge consideration, So this should hopefully, give you the tools that you need to calculate that voltage drop.
57:43 If I've gone over it a bit too messily, there's plenty of even calculators online you can find that will actually let you put in things like your voltage, amps, the length of your wire, choose the wire or the resistance and it'll calculate for you and tell you what wire would be best based on that information that you've given it.
58:06 As with anything it really you need to make sure of your information that you're giving the calculator, be sure on your component amperage rating, the power draw that is going to be pulling.
58:20 That's why we de-rate just to make sure that that is good and it's not like a off chance that it's going to draw exactly the highest amperage.
58:28 And just be sure that when you're adding that information into your calculator.
58:32 Because with anything you put garbage in you're going to get garbage out and it's not going to be useless.
58:37 All the information is out there, especially sorry I guess not always, but with components you'll usually be able to find some sort of information that will help you calculate what you want to know.
58:49 So, as I said with our Ohm's law, you have the other one with power and you will be able to find online charts that have it all together which would look a lot nicer and be a bit more easier to explain probably.
59:03 You don't want to know the words that I'm going in my head that I've learned to remember this all my life, they're not suitable for children.
59:10 If you have something like a light bulb they won't tell you how many amps it's going to draw, they'll tell you the watts that it's outputting.
59:19 But we can use that then, put the watts into our power, we know the voltage that we're going to be running that light bulb at, that will give us our current and we can calculate our wire size and the voltage drop and everything like that.
59:32 All right I think my voice is getting pretty raw at the moment, so I've probably said enough.
59:38 So, let's get into some questions because questions are going to be where I'm going to get stumped.
59:44 All right, so first up we've got MTN Dog Rally, what wire gauge per Bosch 044 if I'm running 32 Tefzel.
59:53 All right well let's go through this.
59:56 First thing you need to know is our Bosch 044 pump.
01:00:00 I've got here, so this is not Bosch 044, but if our hardware should have a Bosch one in here we need to find the information on the pump itself.
01:00:11 Here we go, Bosch 044 700 horsepower pump.
01:00:15 And if we go through here we'll hopefully get some sort of data sheet.
01:00:23 Is it one of the banjo fittings? This is probably not gonna stump and get me in trouble.
01:00:30 All right we might have to look up what's here.
01:00:34 Here we go, outlet flows 276 liters per hour at 3 bar on 12.8 volts drawing 11 amps.
01:00:43 So, this is only giving us one sort of situation, our 12.8 volts drawing 11 amps.
01:00:51 That's probably, you know, we're thinking engine off.
01:00:57 So, we don't, that's gonna be a bit of a worst case scenario because as we increase the voltage with the engine running it's not going to draw quite as much.
01:01:05 But we might have a situation where the pump might be blocked or whatever, so we do want to de -rate that probably by quite a bit considering it's not giving us sort of a worst case scenario.
01:01:12 I mean if we use our calculator here, 11 amps times by 1.2 de-rating by 20%, 13.2, I would say 15 amp.
01:01:23 We'll put that up to 15 amp just to really, you know, give us some headway.
01:01:27 So, now the biggest thing that in our question here, what I can't give you a definite answer on is the wire size because I don't know how long your wiring is going to be.
01:01:39 And that is, especially for a fuel pump, very very critical.
01:01:43 Going back to question, you want to use 32.
01:01:45 I can say that though if we look at... oops, sorry, where am I? Here, okay, we've got out our base amp.
01:01:53 We're going to say maximum, our worst case scenario, say 15 amp.
01:01:58 It may be a bit more than this, probably find a better data sheet that will give you a better indication.
01:02:04 But based on that, our 16 gauge would probably be okay running that amount of amps.
01:02:11 The biggest problem we're going to have with the fuel pump is distance.
01:02:15 9 times out of 10, your fuel pump is going to be one of your longest circuits being, you know, right, at the back of the car.
01:02:21 You might have 3, 4, 5 meters depending on how it's run through the car.
01:02:25 And as we even saw just with 3 meters for a fan, that voltage drop can become quite drastic.
01:02:32 And a big thing with fuel pumps, what's happening in your ECU, if it's an electronically controlled engine, your ECU is making calculations on how much fuel it is supplying using the voltage that it sees and what information you give about the pump.
01:02:51 At a certain voltage, you should be getting this amount of fuel.
01:02:56 If what the ECU is seeing at the front of the car is around 13.5 volts, but then our voltage is dropping drastically by a volt or more to the fuel pump, it's not actually going to be supplying as much fuel as your ECU thinks.
01:03:10 And your ECU is going to then get stuck, it's not stuck, but it's going to be making its calculations slightly wrong.
01:03:15 And in a very worst case scenario, this can then cause the engine to run lean and just a bad day.
01:03:22 So, that is why voltage drop is a very important thing.
01:03:25 And the same, you know, if you're calculating for injectors, it's not such a bad situation because quite a significantly less current draw, so the chances of a big voltage drop is less.
01:03:36 But if you were to really size your wiring way too small, you would start getting voltage drop at your injectors and they wouldn't actually be supplying what your ECU is trying to tell them to.
01:03:47 Having said that, that is probably something I do need to touch on is load types.
01:03:53 So, based on what I've been doing here, fuel pumps and fans and lights, now fans and pumps, they have an inrush current, meaning at the very start of turning them on, they do draw quite a significant more current than what, you know, we say here with the fan being, you know, 10 amp or the fuel pump being 15.
01:04:11 It can get up past 20, 30 amps, that sort of thing.
01:04:15 The thing here is it's for a very short moment of time.
01:04:20 Because the amperage is going over this rating of the wire, it doesn't mean it's going to blow up or anything like that.
01:04:25 This rating is saying it can sustain 10 amps or 15 amps or whatever for a continuous amount of time and the amount of heat that is being produced from the resistance of the wire, it's not going to melt your insulation or anything like that.
01:04:45 Your big inrush of current, it's big, but it's for a very split second of time and it's not long enough to actually produce enough heat to, you know, start melting things and cause a problem.
01:04:56 What it can do is you might have a fuse, it might actually blow the fuse beforehand.
01:05:01 If you say, say if we only put a 10 amp fuse for this fan, its inrush might be up to 20, 25 amps and that could actually blow our fuse.
01:05:09 You can get fuses that are a slow blow.
01:05:11 I think most blade fuses, you know, they're not an instantaneous blow.
01:05:16 They won't see above that 10 amp and go straight away, blow, done, see you later.
01:05:21 They do have a short amount of time where they allow for these inrushes and things to pass through and not cause problems.
01:05:28 So, with that, that is inrush.
01:05:32 When I'm talking about light globes, that is a continuous current, which is probably our easiest, you know, to calculate because we've just got one continuous current of say 10 amps, 3 amps, whatever, and we can use that for our calculations.
01:05:43 Things like our injectors, however, they're a duty cycle.
01:05:48 If you haven't talked about that before, our duty cycle, you're basically applying power to it for a certain amount of time, and then you're releasing that power for another certain amount of time.
01:05:58 And that is your duty cycle, how long the component is on and off.
01:06:02 So, we might look at an injector and the data sheet says that at our specific voltage, it's going to draw 3 amps per se.
01:06:11 Because our injector isn't firing constantly, we only got a short duty cycle, and, or it might not be short, it might be bigger at other points, but we need to take that duty cycle into consideration.
01:06:23 If you have a 50% duty cycle, we're actually only going to be seeing, you know, that 3 amp half the time, so we're not going to be producing as much heat.
01:06:30 And also, if you think about injectors, if you're wiring them all for one power supply, you're not firing all of them at once, unless you're firing batch fire.
01:06:38 Most cases these days, we'll be firing sequential, so it's only, you know, one at a time or two at a time for batch, and we don't need to worry about all that combined current at once.
01:06:47 We need to, in those situations, we do have to go a bit further, look at how the components are actually, working together, and, you know, if they're all going to be drawing current at the same time.
01:06:57 If they are, if it is a batch fire, then yes, you need to take 3 plus 3 plus 3 plus 3, add all your current up, and cake like that.
01:07:05 I've gotten sidetracked, we wanted, the question was about the Bosch 044, so that's a good, that's where these questions sort of, you can come unstuck.
01:07:15 Going just by the information that we've found, we rated it at 15 amps, we can't really just say, hey, 16 gauge is rated to 15 amps, I'm going to throw that in.
01:07:28 You need to work out that voltage drop, and at the end of the day, more wire is never going to be a problem, except for things like space and, you know, money.
01:07:39 We can, I mean, you could run 2 gauge wire for your fuel pump and you're never going to have a voltage drop that's going to be, you know, a concern, but you're running massive wire for, you know, no reason essentially.
01:07:50 So, what we're trying to do, we're trying to compromise, we want to get as close to our rating for the installation and the wire itself, but we still want to provide enough headroom that we can not have voltage drop, we don't have the resistance.
01:08:04 So, we just, we can go through, use these calculations of voltage drop, and basically just step it up until we've got a wire that we're comfortable with our voltage drop.
01:08:14 Like I said, fuel pump, you probably want to get out of that 2%, so we might, we'd probably even go down to a 12 gauge.
01:08:18 And I, personally, I've used, yeah, 12 gauge a lot for fuel pump wiring, if it's a long distance, even down to 10 gauge.
01:08:26 And it depends hugely on the pump as well, like I've also wired up fuel pumps that, you know, don't draw that much more current.
01:08:34 Their worst case might be about 10 amps, and you can get away with, you know, like a 18 or 16 gauge being a longer distance.
01:08:45 Another question...
01:08:52 CTTC4470, SAMILW2275911, is silver-plated, better ampacity corrosion resistance, rated 200C.
01:08:59 Is there a reason beside cost difference to prefer 32 or 16 over 11 that I'm not aware of? Yeah, okay, so there are a lot of these.
01:09:08 The 22759, it's basically a whole series of wire.
01:09:11 I think I do have that here somewhere.
01:09:16 Yeah, here we go.
01:09:17 This isn't even all of them.
01:09:18 Like I said, you're looking at 11, I think.
01:09:21 Not sure if they have that here.
01:09:23 Like I said, this site's got a huge amount of information.
01:09:29 But if we look here, sort of the main differences is, yeah, insulation, how thick it is, what it is actually made out of, and what coating we have on our conductors.
01:09:39 Like you said, the 11 is silver-plated.
01:09:44 Our Tefzel that we're using here, the 32, is tin -plated.
01:09:49 So, they're both copper underneath, but one has a silver plating over it, your 11, which as you say, better ampacity, better corrosion resistance, and the coating is rated to 200C, which is probably that also is in consideration to the silver.
01:10:07 It probably can hold the heat better and doesn't dissipate as much into the Tefzel coating.
01:10:14 All these things are taken into consideration.
01:10:18 From the top of my head, I can't say I've really looked at the 2275911.
01:10:25 Being silver-plated, I can imagine it is more expensive than our tin-plated 32 or 16.
01:10:31 It's probably, yeah, these little things that you've said here, the corrosion resistance, etc., they're generally the biggest differences.
01:10:39 It's not going to be a huge thing like the drastic difference between PVC and Tefzel.
01:10:45 So, at the end of the day, you just take those things into your own consideration.
01:10:49 I see 32 and 16 sold a lot, so that is the other thing.
01:10:54 Our local store doesn't stock 11, so it might be harder to get.
01:10:59 Those are the only real things to take away from that.
01:11:05 Being 200C temperature resistance, that is pretty great.
01:11:11 At the end of the day, you're probably not going to need that much.
01:11:15 As I said, you kind of run your wiring away from heat sources anyway, so you don't do your best to get close to that 200C, but it is going to help, and it will help with things like when you're considering your bundling and where you're running it.
01:11:32 So, to answer your question, any other reasons besides cost difference, it's really just those things that you've listed there.
01:11:40 The better corrosion resistance, the temperature difference and the cost, they're what you take into consideration.
01:11:46 As I said as well, it might be how available it is.
01:11:50 Neither one is probably at the end of the day going to cause you to be a big player as in like, hey I can't use this 32 for my fuel pump, I have to use 11.
01:12:02 It's just going to be what you want to spend and what's easy to get, where you're going to run the wire.
01:12:08 What do we got here? Next one, MTN Dog Rally, same question.
01:12:16 Okay, yeah, so you're saying it would be good for running near an exhaust or something.
01:12:20 At the end of the day, you're paying more money for this silver plated product because you want to run it near an exhaust.
01:12:27 To save yourself money, it might be a lot easier just to run it not near the exhaust, run it away and run it somewhere else.
01:12:33 And then you can use your 32 or 16, which is used in motorsport all the time, it's a very good conductor, there's no reason not to use it apart from, like you're saying, the exhaust if you're running it really close.
01:12:46 It's up to you, if you really need to run it by your exhaust, yeah it might be worth jumping up to that 11 and spending the extra money to allow you to run it near it.
01:12:57 Yeah, I guess to answer those two questions in one, it really comes out to what your situation is going to require.
01:13:06 MJL-21.
01:13:07 If we want to redo really old wiring on an accessory, but don't have much information on the device, is stripping the wire and counting the strands plus measuring the gauge of each strand with calipers a viable method to determine the replacement wire size? In that sort of situation, if you're rewiring the component, unless you're keeping some of the old wire, in that sort of situation, say you've got an old wiper motor from a car, you can't find any information, you'd actually get your multimeter out, set it to your amps, you can run the motor through your multimeter, see how many amps it's drawing or check the resistance, use those calculations I showed you with Ohm's law, that'll tell you what that component is going to draw.
01:13:56 That'll give you a pretty good idea of what the OEM wiring might have been size-wise, but based on that, if you're going to rewire it yourself, do your own calculations and assess the wire for yourself.
01:14:08 Don't just look at what they used before because being old wiring, it might only be like the PVC, so, they might have had to up-size the wire quite a bit because the insulation waters are good, and if you're going to be using Tefzel, you can probably get away with a much smaller wire conductor size because you don't have to worry about the heat melting the insulation.
01:14:30 So yeah, the best thing when you're doing old cars, I've done a lot of Datsuns and things, you're going to rewire it, don't worry about the old wiring, don't use that as your reference, really find your component data.
01:14:42 So, as I said, you really want to know the amp draw power from the component itself and you can measure that by bench testing, that sort of thing.
01:14:53 You can also measure the actual size, but also at the end of the day, you might not know, it might be silver and you might think it might be tin-plated, but it could also be silver-plated.
01:15:04 It's a bit too much up in the air, if you just actually test the component then that's going to give you a better idea.
01:15:12 I do have a note here saying we are running out of time, so I've really got to get through this, hopefully, I can get some more questions.
01:15:18 How much will or does ohms come into play with CAN wires? Can a few extra meters cause any weird readings in a network? Yeah, so this is probably a whole big thing to get into.
01:15:34 You have things like impedance that come into play for CAN wires and that sort of thing.
01:15:41 To answer this quickly, stick to the CAN, what do you call it, the fundamentals principles that you see written everywhere in your ECU documentation.
01:15:50 Keep your stub lengths fairly short and make sure they're twisted together for interference, that sort of thing, and you won't really have to worry about it.
01:16:00 The only time running the main trunk that might come into issues is if you're going down and back down and back down and back and having a really long, long CAN line.
01:16:12 But the main thing is those stub lengths that you want to keep to a certain size.
01:16:18 All right, last two questions.
01:16:19 Wolf's blade again, more or less twisted pair in a club sport custom harness for ECU engage cluster? Was that to do with the last one as well? Sorry that doesn't really make more or less twisted pair in a club sport custom harness for ECU engage cluster.
01:16:36 That's going over my head right now, sorry I'll move on because we're running out of time.
01:16:39 Mr.
01:16:39 Happy Scooters, you're the last question.
01:16:42 Could you go for the average power consumption of the individual components that are wired up in an automotive stuff? Injectors, throttle body, etc.
01:16:50 Etc.
01:16:52 Go for the average power consumption.
01:16:54 Well, that's essentially what you want to do for when you have your injectors and you're going to wire them off from a single wire.
01:16:59 You want to work out what's...
01:17:01 I guess you kind of want to work out the maximum.
01:17:06 In all this sort of situation we're going for worst case scenario, we don't want things to burn up and that kind of thing.
01:17:12 So, you'd work out what's the maximum amount of amps that's going to be going through that wire at once.
01:17:17 And because of our injectors being fired at different times that won't be the total of all the amps, it'll be the total of amps at that actual one time of being fired.
01:17:28 Hopefully, that answers that question.
01:17:32 Hopefully, this has really been a good webinar for you guys and has made some sense.
01:17:37 If there's any more questions, jump on the forums.
01:17:40 Me and the guys get on there when we can.
01:17:42 There's heaps of other people who are smarter and... sorry, maybe not smarter, but they're smart and they will help you answer questions.
01:17:49 If you are really desperate for an answer you can shoot us an email at support at hpacademy .com.
01:17:55 We try and get back to them as much as possible.
01:17:58 This has been a bit of a longer one today.
01:18:00 I hope you've enjoyed it and I'll see you for the next one.
01:18:02 Thank you guys.