Littelfuse, Inc. SYMC Protection Relays 355400

The Quarktwin Technology Ltd. Monitor - Relay Output, part number 355400, is a three-phase voltage monitoring relay designed for applications requiring protection against voltage issues. It operates within a line voltage range of 380 to 480 V AC and features adjustable trip and restart delay settings, as well as adjustable voltage unbalance thresholds. The device utilizes microcontroller technology to continuously monitor voltage conditions and de-energizes its output relay in the event of faults such as single-phasing, high or low voltage, phase reversal, and voltage unbalance. The 355400 model is equipped with a 470 VA @ 600 V AC pilot duty SPDT relay, suitable for heavy-duty applications including pump panels and commercial HVAC systems. It includes four diagnostic LEDs that indicate various conditions, aiding in troubleshooting and ensuring user-friendly diagnostics. The relay is designed to prevent nuisance tripping and allows for staggered motor start-up after faults, which can help avoid low-voltage conditions. Operating temperature ranges from -40¬8 to 70 ¬8C, making it suitable for a variety of environments.