Mep803a ammeter showing zero, no charge

[asulwer]

I checked the fu1 fuse it's good or has continuity. pulling that fuse while Gen is running causes the meter to dip below zero and with the fuse in, it sits at zero.

I have about 27v going to the exciter on the alternator and 28+ coming out of the alternator.

The ammeter has zero voltage at its two terminals.

I am making an assumption the zero voltage at the ammeter terminals is an issue? But where to start?

 

[kloppk]

Everything you describe sounds normal.

Normally when you first start the generator the gauge will go a bit up into the green indicating the alternator is topping off the batteries after starting. It usually goes back to virtually zero when running after that.
28+ volts from the alternator sounds correct. My battery voltage is 28.2 when running.
The Battery Charge ammeter is a -25 to 0, 0 to 50 mV Full Scale meter.
The alternator current flows thru the MT4 shunt. The battery charge ammeter displays the millivolts developed across the shunt.
Full scale deflection into the RED indicates -25 mV. Full scale deflection into the green indicates 50 mV.

 

[DieselAddict]

When you start the generator, does the meter drop below zero?

 

[asulwer]

No it does not dip below zero as I start it

 

[Light in the Dark]

Unfortunately for you, it sounds like the gauge is working properly, as is your alternator. You'll have to put your efforts back to the honey-do list we all avoid when we say we have generator problems.

 

[asulwer]

Thanks to everyone that helped. It's a relief that it's working as expected