DERELL RES-37F-220 | 3 Relay Outputs, Dual Sensor Inputs, Advanced Cooling Controller

RES-37F-220 is a versatile cooling controller with 3 relay outputs (compressor, defrost, alarm) and 2 NTC sensor inputs to separately monitor room and evaporator temperatures.

The device includes compressor protection timing, defrost cycle settings, dual temperature calibration, and one digital input for door alarm, manual defrost, or other logic-based functions.

Application Areas: Refrigeration cabinets, fan coolers, fast freezers, cold rooms, multi-level display fridges, commercial showcases.

▶︎ Technical Specifications

Power Supply: 220V AC
Inputs: 2 x NTC probes (Room + Evaporator)
Outputs: Compressor (NO), Defrost (NO), Alarm (NO)
Control Range: -40°C ~ +150°C
Defrost Type: Electric or Hot Gas (Selectable)
Hysteresis: Adjustable 0.1–20.0°C
Defrost Timing: Interval (d0) & Duration (d3)
Alarm Limits: Low (A1), High (A4), Delay (A6/A7)
Digital Input: 1 dry contact (EA, dEFr, doar, etc.)
Sensor Protection: Timed ON/OFF for sensor errors

▶︎ Editor’s Recommendations & Experience

This device is highly recommended for advanced cooling applications. It accurately handles both ambient and evaporator temperatures independently. The defrost cycle is customizable and supports electric or hot gas systems.

Make sure to configure c0 to c4 parameters carefully for compressor protection. For door-based or external alarms, digital input configuration is very flexible. Sensor wiring should always be shielded and installed away from high voltage lines.

All parameter memory is non-volatile, ensuring stable operation after power failure. A reliable solution for professional-grade refrigeration control.

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