Discussion and questions related to the course Practical Harness Construction - Club Level
Not sure if I missed it in the video, but I was wondering if there was anything more to terminating the star point earth? It appears that you must add the cma or mm^2 area of all the earth wires together in order to calculate the size of circular lug you need and bunch all the stripped wires together before crimping the lug on.
Would you use a hex crimper for this?
If your total cma or mm^2 area of the wires doesn’t match up to a standard size of lug is it a good idea to use filler wires to make up the size?
Is it best to have larger wires in the centre of the bunch and smaller around the outside or it doesn’t matter?
Sorry. The title should read ‘Terminating Star Point Earth’
Yes, it's a case of adding up the over all CMA/mm^2 of the individual wires and specing a ring terminal to match. For the harness in the course I had enough earth wires that I used a 16mm^2 lug with an 8mm hole for an M8 bolt. Yeap, I used a cheap hex crimper from china. I've had good results from it, but it does take some faffing about to use, which is why it isn't in the course.
Often, all your ground wires will have an overall CMA small enough to get away with a smaller ring terminal, which you can crimp using an indent, or w-shaped die crimper.
I have, in the past, used filler wire to get the CMA into a range for a terminal I had on hand, and it does work fine. You need to take into account the physical strength of the wires you;re connecting though, as there wont be the same bulk heading away from the connector to support everything, so you might need to add some strain relief ATUM or SCL to keep it reliable.
Thanks Zac, that answers everything.
Was it a cheap hydraulic crimper you used? I used one of these for all my battery cabling and it worked fine for a small 1 off job. You can get them from the electrical wholesalers in NZ for about $60 +gst https://www.ebay.com/p/Heavy-Duty-Hex-Crimping-Tool-Lx-50b-Cable-Lug-Connectors-Crimper-Range-6-50mm/1273585339
Yeah cheap hydraulic one I bought from Aliexpress as a bit of an experiment. It works, but its not ideal I'd say. That one you've linked looks like it would be a better bet!