Is the ammeter shunt needed?

[Mike D]

This may have been answered, but If you are using the hall effect donut to measure your amps, do you need the shunt?

I am installing a GRT Sport and have the little green donut on the battery lead. I don?t have anywhere to connect the shunt into the GRT, so not sure what use it has. Maybe someone wiser can let me know if there is a reason to leave it in.

Thanks

[Ironflight]

I didn't use a shunt on my GRT installation Michael - just the green "donut" hooked in to the system. Works just fine. I like the donut better than the shunt that we have on Louise's plane - just seems like to much "exposure" for the wires with the shunt...

Paul

[Bill Dicus]

The AFS literature suggests using shunt for main alt/batt and Hall Effect transducer for the #2 alt/batt, which is what I'm doing on my -8. Hope I've got that correct. I agree the shunt is pretty exposed. Seems that it could be covered with some sort of insulation. Has anybody done that?

[elippse]

Originally Posted by Mike D

This may have been answered, but If you are using the hall effect donut to measure your amps, do you need the shunt?

I am installing a GRT Sport and have the little green donut on the battery lead. I don?t have anywhere to connect the shunt into the GRT, so not sure what use it has. Maybe someone wiser can let me know if there is a reason to leave it in.

Thanks

Typically the low-resistance shunt is used to divert a small amount of current into a milli-ammeter to display a reading proportional to the current flow. If you are obtaining this indication from a linear Hall-effect device, there is no need for the shunt. Some install their current sensor between the alternator and the battery, but that will not show battery discharge, only the flow to the buss plus the charge current going into the battery. By installing the current sensor between the battery and the buss, it will show the flow into or out of the battery, charge or discharge. In this case, the alternator is supplying the load, and just a small current of 1A-2A is going into the battery to maintain its voltage. That way if the battery is supplying some or all of the load, it will show a discharge.