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These Contactors are mainly used as High current Switches used between the Battery Pack and Controller. Single Pole/Single Throw. The Contactor Coil Ratings are determined by the voltage input used to switch on the Contactor.
A 12 Volt Coil Contactor could be used to switch a 144 Volt system if the Contactor Specification allows this Voltage Switch. You would need an auxiliary Battery in this System or tap into 12 volts of your Battery Pack (not Recommended).