You need to rewire to a lower voltage at panel or get a transformer that steps down 277 to 110 volts. Make sure wire is sized for new load as well as breaker.
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This is a product that simply screws in to a recessed can without having to rewire or remove the can and converts it to a hanging pendant...
If the question is, can I wire a switch to an existing light fixture (and I must assume that it's something like a pull-chain light fixture), the answer is yes. If the question is, "how do I wire a...