Altech Corp MA12-110V-CU Miniature Electromechanical Relay

The MA12-110V-CU is a four‑digit LED panel ammeter from Altech Corporation that measures AC current in a 1‑phase, 2‑wire system and displays up to 4960 A when used with an external current transformer (CT). It is panel‑mounted and powered from 110 VAC ±20% at 60 Hz, with a 4‑digit, 7‑segment LED display for clear readings. It supports 1 Phase (2 wire) wiring and uses CT Type measurement (external CT required for current > 5 A); for currents up to 5 A, the input range is 50 mA to 5 A. The MA12‑110V‑CU provides an accuracy of ±0.5% of full scale and operates over a frequency range of 45 to 65 Hz, suitable for typical AC mains environments. Display range is 0–4960 A, with current display resolution configurable by the CT primary ratio (typical settings include 0.001, 0.01, 0.1, or 1 A depending on the external CT). Certifications include CE, RoHS, and UL recognition. The MA12 series also includes alternative DC versions with 50 mV or 100 mV shunts for DC current measurements, but MA12-110V-CU specifically targets AC current with external CT for high-current applications. Panel-mounted meters like this are commonly used to monitor mains circuits, feeders, and load current in industrial control panels and electrical distributions.