DERELL RES-37S-220 | Economical Heating & Cooling Controller

RES-37S-220 is a compact, single-relay economical controller designed for simple heating or cooling operations using a single NTC sensor and ON/OFF hysteresis logic.

The device supports 220V AC, 24V DC, and 12V DC supply options and includes a powerful 16A relay output. The temperature control range is wide: from -40°C to +150°C. Setpoint limits and measurement units (°C/°F) are selectable by the user.

Main Features: 4-digit LED display, startup delay, °C/°F selection, adjustable hysteresis, compact body, IP65 protected front panel.

Typical Applications: Basic heating/cooling projects, fan control, resistive heaters, hobby projects, automation panels with space constraints.

▶︎ Technical Specifications

Dimensions: 75x35x75 mm
Power Supply: 220VAC / 24VDC / 12VDC
Relay Output: 1 x Relay 16A / 250VAC (NO/NC)
Sensor Input: 1 x NTC (10k Ohm, 25°C)
Display: 4-digit, 14mm LED
Measurement Range: -40°C to +150°C
Temperature Unit: Selectable °C or °F
Hysteresis: ON/OFF adjustable
Front Panel Protection: IP65
Operating Temperature: 0–50°C

▶︎ Editor’s Notes & Experience

This is an ideal entry-level model for users who need simple and stable temperature control. The relay is powerful enough for direct motor or heater switching.

Display is clear, buttons are responsive, and the structure is durable. For better accuracy, keep the NTC sensor cable as short as possible. Perfect for compact and budget-focused installations.

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