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Old 02-23-2009
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Quote:
Originally Posted by GordMay View Post
To take the 100A Shunt & Ammeter out of the circuit, you could wire a simple DPST “off-on” toggle switch (Blue Sea Systems #8287) in series with the two little shunt wires. Switch “on” shunt in cct; switch “off” shunt isolated. Ammeter shunts typically only draw 50 milliAmps at full scale, so switch ampacity won’t be an issue.
My understanding is that it's not so much a matter of taking the ammeter out of the circuit, but taking the entire shunt out of the circuit. I.e., even if you disconnected the low current ammeter wires from the shunt, you'd still be running ~400A through a shunt that is rated at 100A max, and the docs state that doing so can permanently alter the characteristics of the shunt (i.e. screw it up so that the ammeter doesn't get the correct current sampling).

So I need a way to take the shunt itself out of the circuit (in a way that doesn't involve tools ;-)
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