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Altenator not charging

Practical Motorsport Wiring - Club Level

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Hey! When designing the power system, I laid a wire to excite the altenator directly from the main relay. As a result, there is no charging, the altenator is not excited. By experience I found out that a light bulb is needed in the circuit. With her, the charge appears. However, it is no longer possible to include a light bulb in the circuit. Could adding a resistor or diode to the circuit work if you squeeze it right into the connector? Nissan 350z car

Different alternators have different wiring requirments, if yours is designed with a light (in the field winding circuit?), using a small resistor. I think a 1/4W 83 Ohm would be about right.

Anyone else?

I've seen plenty of 350z with a bulb wired into the harness (one actually located next to the alternator).

My alternator factory circuit does not have a bulb, so I built my custom circuit the same way.

Sometimes the alternator starts up immediately and sometimes it doesn't. When it doesn't, I just rev up to 2k for a second and then the alternator starts working.

You can replace the lamp with a resistor but they generally need to be quite big since the circuit will draw significant load when not charging (200mA). A 1/4W resistor will fry in seconds. You need something like 100ohm 3W.

Adam's right, I dropped a decimal. :-(

No excuse - especially as it would be replacing an ~2W bulb.