Sets the differential allowed before turning the cooling/heating back on (e.g., if set to 2∘C2 raised to the composed with power cap C , heater turns off at set point and on when temp drops by 2∘C2 raised to the composed with power cap C
Run the AT (Auto-Tuning) cycle again or increase the Pb value. Lock parameter is turned on. Navigate to LCK and verify the passcode is set to 0000 . No display power Missing primary line voltage.
Green lower display. Shows the target temperature. OUT LED: Illuminates when the control output is active. ALM LED: Illuminates when an alarm condition is triggered. Button Functions SET Button: Accesses menus and saves parameter updates.
Before diving into programming, it is critical to understand that FourTech produces multiple generations of controllers. While this guide provides universal steps, the official for your specific model is essential for: fourtech temperature controller manual
: Most Fourtech-style controllers feature an "AT" function. When activated, the controller "learns" the thermal characteristics of your system, automatically calculating the best P, I, and D values for stability.
Higher terminal numbers (e.g., 8 through 10) connect internal auxiliary alarm relays. Input Sensor Connection
Allow the system to complete 2 to 3 heating cycles. The controller will automatically calculate the best values for , It , and dt , then save them to memory. 6. Troubleshooting and Error Codes No display power Missing primary line voltage
| Problem | Likely Cause | Solution | | :--- | :--- | :--- | | | Sensor is shorted or temperature too high | Check thermocouple wires for a short. | | Display shows LLL | Sensor is broken or reversed polarity | Swap the two sensor wires. | | Temperature swings wildly | PID not tuned | Run Auto-Tuning (AT=1). | | Unit won't heat at all | Output relay failed or wiring loose | Check terminals 7 & 8 for voltage during heat demand. | | Display flashes 5C.Er | Sensor type mismatch | Check that the input type (e.g., K ) matches your probe. |
Shows current temperature (Process Value) and set temperature (Set Point). Control Modes: Typically Cooling or Heating. Sensor: Generally uses a waterproof NTC probe. 2. Operating Procedures (Setting the Temperature)
If you have landed on this page, you are likely searching for the . Whether you are setting up an industrial oven, a plastic injection molding machine, a laboratory incubator, or a commercial HVAC system, FourTech controllers are renowned for their precision and durability. However, without the proper manual, programming these sophisticated devices can feel like deciphering an ancient script. OUT LED: Illuminates when the control output is active
Sets the upper-limit temperature threshold to trigger Alarm 1. Alarm 1 Low
Use a Solid State Relay (SSR) for precise PID control or a standard mechanical relay for simple ON-OFF tasks. 2. Front Panel Layout
Modify each digit until the SV display reflects your target temperature.
The output device (Relay or SSR) may have failed in a closed/shorted position. Disconnect power immediately and test the relay or SSR using a multimeter.
The upper display (usually red). Shows the current temperature measured by the sensor.