Hello everyone.
I am an electrician in Ireland, and came across a problem a few days
ago.
I was investigating why a motor of a washing machine in a commercial
laundry would not spin correctly and found the cables going from the
tacho generator to the control electronic were causing the problem, I
rerouted the cables and found all worked ok.

I suspect some form of mutual inductance, the tacho cables only carry
a small voltage, but was in a loom with many main voltage cables, Did
anyone ever come across a similar problem ? If so what is the best way
of identifying the problem, would an oscilloscope be required. Even
though I know I sorted out the problem I would like to know the best
way of testing for this problem .

Thank you for all your help
Seamus