PA24-250 shunt value

[Russell Knowles]

[AlanBreen]

Hi Russell,

I went through this very same issue 12 months ago when I fitted an EI volt/ammeter in our PA30. From memory, after some testing I figured it to be a 100 amp shunt.

I'm not sure where the circuit breakers are on the 250, on the PA 30 they are under a flap on the cabin floor just behind the nose wheel bulge. The shunt is underneath the CB's.

It is my guess that Piper used the same shunt on all of the Comanches. When you see it you will see that it is not very high tech. I would suggest that the amp readings are a bit arbitary, even though they would still be very useful as they are still relative to whats happening to your electrical system.

The EI uint is certainly worth having. Just be sure you get the wires to the shunt the correct way round otherwise you will see a charge when in fact you have a discharge, the instructions are not all that clear from memory.