mind_the_goat
Established Member
Non woodworking related motor question.
I have a bi-directional tumble dryer which has just developed a fault. The motor runs in one direction but not the other. pulling it apart has revealed the following:
It's a squirrel cage motor with 2 coils and a start/run capacitor, it has 3 wires, a common and 2 lives, rotation is reversed by applying power to one or the other live, with the cap between the 2 lives.
resistance between common and coil 1 is about 10ohms, common and coil2 is about 18ohms, suggesting either a fault different run and start coil windings.
No sign of burnout on the motor coils.
With the belt removed the motor appears to run fine in one direction but in the other direction it buzzes and kicks intermittently and irregularly, between the short kicks there is no detectable torque. it heats up fairly rapidly in this mode.
Not sure how much torque it has in the running direction, one test I missed.
Could this simply be a capacitor fault with the imbalance in the coils causing the different behavior? Can anyone explain this?
I have tried to Google this but not found anything matching these symptoms. Obviously there are more appropriate forums to ask this but I do believe there one or two people on this forum that might be able to give a proper explanation.
I have a bi-directional tumble dryer which has just developed a fault. The motor runs in one direction but not the other. pulling it apart has revealed the following:
It's a squirrel cage motor with 2 coils and a start/run capacitor, it has 3 wires, a common and 2 lives, rotation is reversed by applying power to one or the other live, with the cap between the 2 lives.
resistance between common and coil 1 is about 10ohms, common and coil2 is about 18ohms, suggesting either a fault different run and start coil windings.
No sign of burnout on the motor coils.
With the belt removed the motor appears to run fine in one direction but in the other direction it buzzes and kicks intermittently and irregularly, between the short kicks there is no detectable torque. it heats up fairly rapidly in this mode.
Not sure how much torque it has in the running direction, one test I missed.
Could this simply be a capacitor fault with the imbalance in the coils causing the different behavior? Can anyone explain this?
I have tried to Google this but not found anything matching these symptoms. Obviously there are more appropriate forums to ask this but I do believe there one or two people on this forum that might be able to give a proper explanation.