Franklin’s motor literature talks about a Subtrol Sensor; what is that?
The Subtrol Sensor is a thermostat and transmitting device buried inside certain Franklin Electric 3-phase, 6- and 8-inch submersible motors. The Subtrol Sensor is used in combination with Franklin’s SubMonitor protection device. If the internal temperature of the motor becomes too high, the thermostat turns on the transmitter. The transmitter then sends a signal up the motor wires, which is picked up by the SubMonitor in the pump panel. By using a Subtrol equipped motor and the SubMonitor, you get high temperature protection without running extra wires down hole.