ATC Diversified Electronics, a division of Marsh Bellofram Corporation, introduces the new MAR Series Motor Auto-Restart Relay. It provides automatic restart to a motor by bypassing the start switch to re-energize the M1 starter coil following a momentary drop or interruption of the control voltage.

 

MAR Series is ideal for industrial production processes with critical components not in a hazardous area and without permissive circuits. By reducing the need for manual restarts of critical operations throughout a process facility, the devices can easily save customers hundreds of thousands of dollars annually in lost productivity.

 

The MAR Series is suitable for a multitude of industries, offering different output interval restart ranges, restart delay ranges, an option for O/L relay L2 disconnect feature, and the choice of 8- or 11-pin plug-in versions.

 

Restarts can be staggered so not all motors come back online all at once, minimizing burden on power capacity. All models are specifically designed to address an undervoltage or power interruption period no greater than 4, 6, or 10 seconds long. The device’s plug-in format sits in a socket and is easily changeable. An optional overload neutral disconnect feature offers protection in case a thermal overload relay senses a high current or temperature condition. Subsequent closure of the circuit via the overload relay will not cause an automatic restart.

 

The MAR Series easily and economically replaces the need for manual restarts. When control voltage drops below the undervoltage trip point while the motor is running, the delay begins. If control voltage returns above the restart voltage point before the delay expires, the adjustable restart delay begins. Upon expiration of the restart delay, the internal relay energizes for the duration of the output interval providing restart. As an additional safety feature, if control voltage fails for longer than the undervoltage time delay or the motor was not initially running when control voltage failed, the unit will not restart the motor after restoration of power. This relay distinguishes between control voltage failures and stop pushbutton operations. A stop pushbutton operation de-energizes the output relay and terminates the timing sequences preventing an automatic restart.