RET-77-S-220V ▪︎ Multifunctional PID Boiler Thermostat

          PV: 128
        

AL1 AL2

        SET: 120
      

Set Value: 120°C

SSR Output:

NOTICE: This product is part of our old series and is provided only for backup use. Please check similar products for new projects.

Description: RET-77-S-220V is a dual-display, multifunctional boiler thermostat with PID algorithm. It supports various thermocouple types and optional Pt100 RTD input. Auto PID tuning, SSR output, and up to two alarm relays are available. Both PV (measured) and SET (target) temperatures can be viewed simultaneously on the display.

Power Supply: 230VAC (+10% ~ -20%) 50/60Hz
Panel Size: 72mm x 72mm x 82mm
Input Types: J, K, T, S, R thermocouples and Pt100 RTD
Accuracy: ±0.5% FS, ±1 digit
Display: Dual LED (4-digit 14mm for PV + 4-digit 12mm for SET)
Outputs: 1 Control Relay + 1 or 2 Alarm Relays

[SET VALUE ADJUSTMENT]

Press the SET button once. The screen will display the target temperature, and a dot will blink at the top-left. Use "+" or "−" to adjust the value.

[ACCESSING PARAMETERS]

Hold the SET button for 4 seconds until “E n G c” appears. Enter "11" to unlock parameters. Use ↑ / ↓ to scroll, and P to edit. Short press P to return.

[IMPORTANT INSTALLATION NOTES]

After any parameter change, disconnect and reconnect the power to apply the settings. The device has no internal overcurrent protection—external safety devices are required. Ensure input voltage, ambient temperature, and relay loads are within safe limits.

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