Technical Guides · 2025-06-07
How to Change Deviation Alarm to Absolute Value Alarm on TC5 Temperature Controller
Learn how to switch the TC5 temperature controller from deviation alarm to absolute high alarm mode. This guide includes step-by-step instructions and a video demo.
The TC5 series temperature controller offers flexible alarm configuration, supporting both deviation-based and absolute-value alarms. In many industrial applications, an absolute value alarm is easier to monitor because the threshold is a fixed temperature rather than an offset from the set value (SV).
This guide explains how to change the upper deviation alarm (Ad1) into an absolute value high alarm on the TC5 controller, step by step.
Video Guide
Watch how to configure the absolute alarm setting on the TC5 temperature controller.
Before You Start
- Confirm the alarm output is wired correctly to your external buzzer, indicator, or relay.
- Check that the input sensor type and measuring range are set correctly. The TC5 supports multiple sensor types (K, J, PT100, etc.).
- Decide the exact alarm temperature you need, because an absolute alarm triggers at a fixed value regardless of the SV.
Step-by-Step: Absolute Alarm Setting
1. Enter parameter setting mode.
Hold the SET button for 3 seconds until the P-1 menu appears.
2. Open the P-2 menu and find the alarm type parameter (Ad1).
Press ▲ to enter the P-2 menu, then scroll to parameter Ad1 using the ▲▼ keys.
3. Change the value from 1 to 5.
- 1 = Deviation alarm (relative to SV)
- 5 = Absolute value alarm (fixed temperature)
4. Confirm and exit.
Press SET to save, then hold SET for 3 seconds to return to the main screen.
Example
If your process must never exceed 180°C, set Ad1 to 5 (absolute value alarm) and configure the alarm value to 180. The controller will trigger the alarm whenever the measured temperature reaches 180°C, no matter which set value you are running.
Common Problems
- Alarm never triggers: confirm Ad1 is set to 5, the alarm value is correct, and the alarm output wiring is properly connected.
- Alarm triggers at the wrong temperature: the parameter may still be in deviation mode (Ad1 = 1), so the alarm value is treated as an offset from the SV instead of a fixed temperature.
- Displayed temperature looks wrong: check that the input sensor type and range settings match the connected sensor.
FAQ
What is the difference between a deviation alarm and an absolute alarm?
A deviation alarm triggers at an offset relative to the set value (SV), while an absolute value alarm triggers at a fixed temperature you define, independent of the SV.
Which parameter switches the alarm mode on the TC5?
Parameter Ad1 in the P-2 menu. Set it to 1 for a deviation alarm or 5 for an absolute value alarm.
Can I connect the alarm output to an external buzzer or relay?
Yes. Make sure the alarm output is wired correctly to the external buzzer or relay before enabling the alarm.
Related Product
This guide applies to the TC5 Series White LED Display PID Temperature Controller, which supports multiple input types (K, J, PT100, etc.), relay or SSR output, and flexible alarm configuration. For wiring help, documentation, or one-on-one support, please contact our team.