The Sensata RP-12A 277v high sensitivity dedicated voltage 3 wire thermal protector.
The 3 wire Sensata RP-12A is for277v Dedicated Voltage The black lead wire is always connected to the input live wire The white wire is the common which is permanently connected at the factory with an extra six inch piece of wire of the same color The third wire of the Sensata RP-12A is permanently connected to the live side of the load