Eliwell Sb655 C Manual

| Terminal | Label | Function | |----------|-------|----------| | 1-2 | Power | 230Vac supply (L, N) | | 3-4 | Probe | PTC/NTC temperature probe | | 5-6 | Digital input | Door switch or generic alarm | | 7-8 | Defrost | Defrost relay (NO) | | 9-10 | Compressor | Compressor relay (NO) |

Note: For 12/24Vac models, refer to model suffix.

In the world of commercial refrigeration, precision and reliability are paramount. The Eliwell SB655C is a ubiquitous controller found in display cases, cold rooms, and beverage coolers worldwide. Known for its versatility, this microprocessor-based controller manages temperature and defrost cycles with high accuracy.

However, like any sophisticated electronic device, the SB655C is only as effective as the person programming it. Whether you are a technician troubleshooting a fault or a business owner trying to adjust a setpoint, understanding the Eliwell SB655C manual is essential. eliwell sb655 c manual

This article breaks down the key aspects of the controller, simplifying the technical jargon found in the official documentation.

Here is a table of the most critical parameters. Set these correctly to avoid compressor short-cycling or product loss.

| Code | Parameter Name | Description | Typical Range | Recommended Setting | | :--- | :--- | :--- | :--- | :--- | | SP | Setpoint | Desired controlled temperature | LS to US | 2.0°C (cooler) / -18.0°C (freezer) | | Hy | Hysteresis | Differential (cut-in – cut-out). Compressor starts at SP+Hy, stops at SP. | 0.1 to 25.0°C | 2.0°C (reduces cycling) | | LS | Minimum Setpoint | Lower limit to lock SP | -50 to US | -30°C (freezer) / 0°C (cooler) | | US | Maximum Setpoint | Upper limit to lock SP | LS to 150°C | 8.0°C (cooler) / 0°C (freezer) | | OdO | On Delay Output | Delay before energizing output after power-up | 0 to 250 min | 2 min (protects compressor) | | dLy | Delay | Minimum off time for compressor | 0 to 60 min | 5 min (crucial for compressor life) | | PA | Password | Access code for parameter menu | 0 to 199 | 3 (default) | | C_F | Temperature Scale | Celsius or Fahrenheit | C / F | C (or F for USA) | | S1P | Probe 1 Type | Type of temperature probe | PtC / ntC | ntC (usually for NTC 10k) or PtC | If the SB655 C is beeping or flashing,

Note: Additional parameters for defrost (if using an external SSR/relay) and digital inputs exist but are rare on the base SB655 C model.

If the SB655 C is beeping or flashing, here is what the manual says:

| Error Code | Meaning | Solution | | :--- | :--- | :--- | | P1 | Probe 1 (Ambient) shorted or open circuit. | Check wiring on terminals 1 & 2. Replace probe (10k NTC). | | P2 | Probe 2 (Evaporator) fault. | Check wiring on terminals 3 & 4. Jumper between 1 & 4 present? | | HA | High temperature alarm (exceeded AL2). | Check if door is open, condenser is dirty, or gas is low. | | LA | Low temperature alarm (below AL1). | Check if setpoint is too low or if probe is unplugged in warm air. | | EE | Internal memory failure. | Controller is faulty. Replace SB655 C unit. | | cEF | Defrost timeout – evaporator did not end defrost. | Defrost duration (c5) too short, or heater is burnt out. | | dor | Door open alarm (if digital input enabled). | Close the door or check door switch terminals 5-7. | relay outputs for compressor and defrost

Overall Verdict:
A functional but dense technical manual. It contains all necessary information for installation, programming, and troubleshooting—but lacks clear organization or real-world examples, making it challenging for first-time users.

The Eliwell SB655C is a microprocessor-based digital controller designed for temperature control in medium/low temperature refrigeration units, cold rooms, and HVAC systems. It features a dual display (setpoint/actual temperature), relay outputs for compressor and defrost, and configurable parameters.

Key Features: