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Back-up Battery Switching

I am attempting to design a circuit that monitors the Line voltage and switch a 12V SLA to the load in the event of a power outage. I am using a LM311, 12V single supply with hysteresis. to turn on a relay that is sourced by a 2N3904. Needless to say I am having a difficult time getting it to work. I am using a 12V reference on the inverting input which I expect would keep the output in a low state. However, that is not the case. I am getting near Vcc voltage at the output. What is wrong with my design? I have tried several different approaches with other comparators including LM339 all with the same result. I have used formulas culled from component manufacturers' websites and various other sources to determine the resistor value for the hysteresis network.