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[terrynbama]

Would there be a problem with either the Grinch controller or the ssr controlling the coil of a contactor relay for running a motorized display?

[BertS]

There shouldn't be too much of a problem using a contactor. Having said that, you will most likely have to use a contactor with 120 VAC to control it. A SSR can be powered by your computer and it in turn can control your contactor. One note of caution. Use a MOV placed across the two terminals for your contactor coil. Every time the contactor de-energizes, it produces what is know as a back emf. This happens because the magnetic field in the contactor collapses and as it's collapsing, it induces a voltage across the coil in the opposite polarity of the coil. The problem is that the induces voltage can be considerably higher than the voltage used to pull the coil in. If you use a 120 volt coil, when it de-energizes, it can produce a spike of several thousand volts which will cause other circuit parts to fry. The MOV clamps the reverse voltage to a tolerable level.