Tony Williams wrote:

Might be useful to look at the LEM Hall Effect Current
Sensors. This would do isolated current sensing with
minimum voltage drop. eg, Radiospares 257-414 is 10V
dc out for 200 Ampere-Turns full scale input. Simply
pass 20-turns (of insulated flexible wire) through the
central hole and it is 10V out for 20A in. The voltage
drop caused by the sensor is just the resistance of 20
turns of wire.


That's a great idea, thanks. 257-414 is discontinued, but there are
quite a few other suitable ones.


--
Grunff