Strong Electric

Technical Guides · 2026-03-02

Technical Guide: Unit Conversion (℃/℉) on TC3-401T Temperature Controller

Technical Guide: How to quickly switch between Celsius (℃) and Fahrenheit (℉) on the TC3-401T Temperature Controller. This tutorial covers the essential LCK 190 unlock code and CF parameter configuration to ensure precise thermal management for your industrial applications. Presented by Strong Electric.

Introduction:

For engineers and technicians working across global markets, the ability to switch between Celsius (℃) and Fahrenheit (℉) is a fundamental requirement. At Beijing Strong Electric, we prioritize precision and user-friendly operation. This guide provides a direct walkthrough on how to modify the unit settings on the TC3-401T series.

Quick Setup Steps (The 'LCK 190' Method)

If you prefer a text-based guide, follow these steps to unlock the hidden parameter menu:

1. Enter Configuration Mode:Press and hold the [SET/TEMP] button for approximately 3 seconds until the parameter code appears on the display.

2. Unlock the Parameters (LCK):Navigate to the LCK parameter. Using the Up/Down arrows, change the value to 190. This code is essential to prevent accidental modification of critical system settings.

3. Access Unit Settings (CF):Scroll through the menu until you see CF.

  • Set to 0: For Celsius (℃)
  • Set to 1: For Fahrenheit (℉)

4. Confirm and Exit:Long press the [SET/TEMP] button to save. The controller will restart its display with the new units applied.

Beijing Strong Electric’s Insight: Why the Lock Code Matters

From an industrial perspective, the 'LCK 190' barrier is a design choice that balances accessibility with operational safety. In high-stakes manufacturing environments, accidental unit switching can lead to catastrophic thermal errors. We recommend that unit conversion only be performed during initial machine commissioning or by authorized maintenance personnel.

Need Further Technical Support?

At Beijing Strong Electric, we don't just sell components; we provide solutions. If you encounter issues with calibration or relay configuration, our engineering team is here to help.



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