True-rms Voltmeters measure to 0V for complex AC voltages

Conventional average-responding AC Voltmeters are limited in that they only produce accurate readings when measuring ideal sine-wave voltages. The DMS-20RM series can also measure and accurately display the true-rms value of triangle waves, square waves or other irregularly shaped waveforms with a full scale accuracy ±of 0.4%. Also, unlike average-responding AC Voltmeters, the new modules from Murata Power Solutions are able to measure down to 0V as they use their own integrated, independent power supply that is fully isolated (up to 2kV) from the input AC signal.

The four-wire DATEL DMS-20RM series is available with a choice of three input ranges of 20VAC (with 0.01V resolution), 200VAC (0.1V resolution) or 300VAC (1V resolution). Depending on their application, customers can choose modules that operate from a supply voltage of either 85 to 264VAC or 10 to 40VDC. No external isolation transformers or auxiliary power supply conditioning components are required for the fully self-contained modules.

Rugged, fully encapsulated polycarbonate housings make the DMS-20RM series both moisture and vibration resistant. A large, three-and-a-half digit 9.4mm (0.37in.) bright red LED display allows easy reading of measurements from distances of up to approximately four metres (12 feet). Overall dimensions of the new modules (excluding PCB) are 35mm x 22.4mm x 25.4mm deep (1.38in. x 0.88in. x 1.00in. deep) and the units are packaged in a red filter case with a built-in bezel. Operating temperature range is -25ºC to +60ºC.