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TR2/3/3A Question on wiring Denso alternator through ammeter

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T

TuffTR250

Jedi Warrior
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I have installed a Denso 8162 alternator on my TR3 and I currently have the "B" post connected directly to the solenoid with an 8 gauge wire, thus bypassing the original wiring and ammeter. The question I have is can I connect a wire from the "B" post of the alternator to one side of the ammeter and then run a similar size wire from the other post of the ammeter to the solenoid, i.e. battery cable connection? Will that allow my ammeter to work correctly with the Denso alternator?

Another question, I was previously using a GM alternator and for that I put a 3.5 inch 16 gauge wire shunt between the posts of the ammeter as per a BCF forum posting. Will that shunt be sufficient for the Denso alternator charging the battery through the ammeter?
Thanks,
Bob
 
The attached sketch shows what I would do. You need to put the ammeter into a spot where it reads charge/discharge current. I'm assuming that the alternator you are using is like most I've seen, with an internal regulator and a separate terminal for the ignition warning lamp.

I didn't include the starter cable in the sketch but it attaches as usual to the battery terminal, to the left of the ammeter in the figure, NOT to the right.

As for the ammeter--you can extend its range with a shunt, but if you just install a random piece of wire, it won't be accurate. It will tell you only whether the system is charging or discharging, but the current reading won't be reliable. Unless you expect to use a large amount of current, I'd leave the ammeter alone. You might pin in occasionally, but I don't think you'll damage it. If you need a higher current range, I'd replace the ammeter with something having the necessary range. Or, find someone who can measure and calculate the right value of the shunt.
 

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An easier way to get the operating information you need is to use a TR6 (or similar) Voltmeter and switch to the convex glass from your TR3 ammeter. Monitors Volts and looks correct.
Steve
 
Thanks Steve! Based on the recommendation of Dan Masters in his Triumph TR250-TR6 Electrical Maintenance Handbook, I am thinking of sticking with the ammeter which Dan Masters says "will tell you exactly how much current is going into your battery, if it's being charged, or how much is going out of your battery if it's being discharged". I want to make sure I don't fry my ammeter with wrong wiring hookup.
Bob
 
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