I have a problem with a contactor (relay) dropping out in an industrial 
control system. The contactors have 24VAC coils. I have hooked an 
oscilloscope to the 24V line and it appears to not have an issue with 
sagging, but it's hard to tell even on an oscilloscope when the event 
could be happening for just a few mS.
Is it common for contactors to wear out in a method that prevents them 
from staying on, or should I be looking closer at the circuit that 
controls the coil?
The contactor is supposed to be latched with another smaller relay that 
is fed by a momentary switch. After several attempts at getting it to 
stay on, it will eventually stay on for an extended amount of time 
(presumably when something warms up?) and perhaps drop out at an 
inopportune moment.
I know I haven't provided a lot of info but hopefully someone has had a 
similar issue - I don't have much experience with this.
Thanks,
Martin K

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