DERELL RES-37-D-220 | Dual Relay Cooling & Defrost Controller with Twin Sensor Inputs

RES-37-D-220 is a professional-grade dual relay controller designed for cooling and defrost control. One relay controls the compressor, while the other is used for either defrost management or alarms.

With dual NTC sensor inputs (Room + Evaporator), it can intelligently manage defrost based on sensor values and time. The device supports electric or hot gas defrost. Manual defrost can also be initiated via keypad or digital input.

Typical Applications: Commercial fridges, cold rooms, display cases, refrigerated cabinets with active defrost systems

▶︎ Technical Specifications

Dimensions: 75 x 35 x 75 mm
Power Supply: 220VAC / 50-60Hz
Compressor Output: 16A / 250VAC (0.75HP supported)
Defrost Output: 8A / 250VAC (electric or hot gas)
Sensor Inputs: 2 x NTC (Room + Evaporator)
Temperature Range: -40°C to +150°C
Display: 4-digit 12mm LED
Front Panel Protection: IP65
Alarms: Visual + optional buzzer
Digital Input: Door, Alarm, Manual Defrost, Direction Switch

▶︎ Editor’s Notes & Experience

This model is an ideal solution for systems that require dual output control. The defrost output can be used flexibly for heating elements or hot gas solenoids. Two independent sensors increase system reliability and precision.

Evaporator sensor logic ensures safe defrost termination. This is a must-have for systems where continuous operation and ice-free performance are critical.

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