The Laureate Model RMS is a UL-listed, 4-1/2 digit, true RMS panel meter which provides 0.15% ± 1 count accuracy for AC voltage or current signals from 10 Hz to 10 kHz. It is suited for AC applications where there is considerable distortion of current waveforms from nonlinear loading. The input is AC coupled to read only the AC component, such as ripple on a power supply.

The unit provides five AC RMS voltage ranges from 200.00 mV to 600.0 V full scale, and four AC RMS current ranges from 2.0000 mA to 5.000A full scale. Precision circuitry is used to compute the root-mean-square of complex waveforms. Spikes up to 2.4 times the maximum of each range are accurately measured, providing a crest factor (Vp / Vrms) of 240 for a signal amplitude of 1% of full scale, decreasing to 2.4 at 100% of full scale.

High common mode rejection allows stable readings with current shunts located on the high side of the line. Five Amp input capability allows the output of 5A current transformers to be applied directly to the meter. The current reading can easily be scaled to display the input to the current transformer. Digital scaling and calibration eliminate zero and span drift associated with potentiometers in non-microcomputer based meters.

Options include dual relays for control or alarm, isolated 4-20 mA and 0-10V analog outputs, and an RS232 or a dual-connector RS485 port for data communications with a host computer or PLC. Modbus RS485 is fully supported.

Laureate meters can be powered from 95-240 Vac, or optionally from 10-34 Vac or 10-48 Vdc. They are available with red or green LEDs. They are housed in a 1/8 DIN case that meets NEMA 4X (IP65) specifications from the front when panel mounted. Any setup functions and front panel keys may be locked out for simplified usage and security.

The base price is $255. For more information and pricing of options, visit www.laurels.com/acmeter.htm