The Model 2601 Voltage Sensor is a single-setpoint under voltage monitor. Input voltages above the setpoint will cause the output contact to energize and the LED indicator to illuminate. Input voltages below the setpoint will cause the output contact to de-energize and the LED indicator will go off. The 2601 Voltage Sensor is available in AC or DC versions. AC models of the 2601 are not frequency sensitive and can be used on systems from 50 to 400Hz. The voltage level is screwdriver adjustable over a wide operating range.