means for opening {HEAD ~ the breaker} in {TAIL ~ response} to the output signal of the OR gate, thereby opening the breaker in response to either one of the power supply interrupting signal and the breaker opening command 
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means for opening { HEAD ~ the breaker } in { TAIL ~ response } to the output signal of the OR gate , thereby opening the breaker in response to either one of the power supply interrupting signal and the breaker opening command
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH