The document describes the DMS-EB-RMS board, which allows the true rms value of ac signals to be displayed on 5V-powered DMS-30PC/LCD digital voltmeters. The board has an input range of 0-750Vac for ±2V meters (1Vac resolution) or 0-199.9Vac for ±200mV meters (0.1Vac resolution). The board also accommodates user-installed modifications such as input-scaling resistors and isolated +5V dc/dc converters.