Alan. A

Hi Adrian Sounds like that's a 25K potentiometer, a variac would be marked with voltage and current ratings not resistance ! If possible remove it and check resistance as it's turned. When potentiometers are worn that would give you the fault your describing. Then go to farnell and get equivalent, same resistance, No. of turns, shaft size etc. I know it's less than a year ago when I looked at my friends but I'm a bit sketchy, I'm sure her pedal was connected to a variac rather than a potentiometer. Maybe a later or earlier model ? Hope this of help Alan

Thanks for getting back Zak. I was thinking because the output from the speed control to the field is 40v (should it not be around the 200 mark ? ) that is why the current is higher. Motor and wheel spin ok by hand and motor checks out ok with megger and voltmeter. Like I said I’m not familiar with a dc shunt motor.

Hello I hope you don't mind me jumping in on this topic. I have been asked to have a look at a friend's Podmore P6706 which keeps tripping the trip on the side of the machine. I measured the current at the trip when the wheel is turning and I am getting 6A, the trip is rated at 2A. Motor seems to check out ok but on the field output from the controller when running I am only getting 40V the armature voltage varies between 0-60V depending on the position of the pedal. It's the first time I have come across a DC shunt motor but from what I've read the field winding should have full voltage (230v). Which leads me to think there is a problem with the motor controller. Zak would it be possible to get the circuit diagram you have just in case I'm missing something. Thanks