Can we use 220V/60Hz Solenoid on 220V/50Hz supply?
I belive this question will apply to any solenoid/relay.


Any AC wound component designed to work at 60 Hz CANNOT be assumed to work properly at 50 Hz. Core saturation is the big thing here. With the lower frequency, more current will be taken and the core may indeed saturate significantly. This may produce too much heat and losses that results in a shortening of the device's lifespan. 

Ask your self why someone designing a solenoid for 60 Hz would put more metal into the core the ensure it works fine at 50 Hz. If the data sheet says it will work then that's another issue BUT as a piece of general advise, you cannot assume it will.

Also, at 50 Hz it may just begin to produce 50 Hz audible sounds - the solenoid armature is mechanical and has inertia and at 60 Hz it may be a lot quieter than it is at 50 Hz.