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Amp meter for T7


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Has anyone fitted an Ampmeter?

I have installed a lot of extra electrical things especially LED lighting.

I would like to monitor the charge rate and know if I'm approaching overloading the alternator.

This shouldn't happen though, I have about 120 watts of extra load connected, and I understand the alternator can produce 410 watts.

Any thoughts on this idea

Thanks Keith

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Most people just put volt meters on their bikes.  When the voltage drops below 12.7 you know you’re pulling more than the stator can provide and are running on battery. Motorcycle stators are different from car alternators. They pump out the same amount of energy regardless of draw on them. Any power not used by the bike’s electrical system gets shunted to ground by the regulator rectifier and / or gets converted to heat by the regulator/ rectifier. 

So adding additional load to the electrical system doesn’t really stress the stator any.  All you are doing is using energy that would otherwise be wasted. The only risk of pulling more current than the stator can provide is not charging the battery. 
What typically kills stators is high resistance which creates heat in the stator and melts the insulation on the windings causing the stator to eventually short out. 

So if you are worried put a small volt meter / USB plug in the accessory plug and keep an eye on the voltage.  You can actually test the draw in your driveway with a volt meter without needing to install one.
Start the bike, and then turn on every accessory, the high beams and the hazard lights and check the voltage at the battery with a multi meter. Then turn off all the accessories and extra lights and check the voltage at the battery again with the bike still running. If both voltages are the same, then you aren’t drawing more than your stator can provide. 

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Aye stick a volt meter/usb charger in the spare accessory port opposite the cigarette lighter socket. Gives a volt meter to look at when the road gets boring and a handy dandy usb charger 

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Yes I appreciated your quality reply.

I didn't know excess current not used is shunted to ground. That's interesting.

I have measured the voltage at the battery terminals with the bike running and all accessories turned on, and off.

I had 12.82 VDC, with motor running, and this drops to 12.65 VDC when I switch all my extra lighting on.

Interestingly, I noticed no increase in voltage between when idling, and when revving the engine  accessories on and off, so that seems to prove the charging circuit is designed to be clamped to a specific load (current draw), via the regulator/ rectifier.

I had an idea to install a small 0 - 100A Hall effect amp meter, where I could just insert the sensing coil around the negative conductor next to the battery, and run a couple of fly leads up to a display mounted somewhere. 

I have an amp meter in series with negative battery lead on my old bike, and it works a treat.

I like to see voltage and current, if I can.

Cheers Keith

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