: 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.
Before you power up, ensure your wiring matches the controller’s requirements. fourtech temperature controller manual
A: First, check the LCK (Lock) parameter. If it’s set to 1 or 2 , the buttons are locked. Set to 0 . If that doesn’t work, cycle power. If still locked, consult the manual for a hardware keylock jumper. : Most Fourtech-style controllers feature an "AT" function
Always use shielded cable for thermocouple extensions. Run sensor wires separately from power wires to avoid electrical noise, which causes erratic readings. A: First, check the LCK (Lock) parameter
| Parameter | Name | What it does | Typical Setting | | :--- | :--- | :--- | :--- | | | Alarm 1 | Triggers a relay if temp exceeds this limit | 5-10° above SV | | P | Proportional Band | How aggressive the controller reacts | Default (often 30) | | I | Integral Time | Removes long-term error | Default (often 240) | | d | Derivative Time | Prevents overshoot | Default (often 60) | | t | Cycle Time | How fast the SSR/Relay switches | 1 sec (SSR) / 20 sec (Relay) | | LCK | Lock | Prevents accidental setting changes | 0 (Unlocked) / 1 (Locked) |
Connect to the rated voltage (e.g., 220V or 110V AC).
A good manual also addresses integration and customization. Many controllers now feature communication protocols that enable integration into supervisory control systems and data historians. Documentation of Modbus register maps, communication settings (baud rate, parity, node addressing), and example queries empowers system integrators. Customizable alarm logic, multi-stage control, and event logging should be explained with examples and sample configurations so users can adapt the controller to their processes without trial-and-error.