NK Technologies VTU voltage transducer allows you to measure DC or AC circuit voltages to 1200 volts with one sensor. This sensor produces an analog signal directly proportional to the RMS voltage making it a very valuable tool to spot issues with power generation (conventional and alternative sources) like brown outs and phase loss. The voltage will be present on the line side of a disconnect even when the breaker or switch is open. NK Technologies VTU-DIN Series Voltage Transducers are high-performance True RMS transducers for sensing voltage in single, three-phase or DC installations.