Originally Posted by zephyr9900  Is there such a thing as a sticky contactor? They seem to me to be a kind of heavy-duty relay, and I know relays can have sticky contacts. Are there any other problems contactors can have? I don't think it is a case of low voltage, because the other contactors always work reliably. |
It should be easy to trouble shoot by measuring the coil voltage, what does the contactor coil use voltage? AC DC?
If a AC contactor does not fully pick up, i.e. the armature sticks, the coil will either over heat or burn out.
If DC then it may not be fully engaging, again, I would trouble shoot using voltage measurements first.
If this is a new contactor, it is unlikely that you have burnt contacts, in a VFD type application, the contactor should pick up under relatively low load,
as the spindle motor command should occur after pick up.
Systematic trouble shooting by voltage readings should pin-point the problem.
Al.