THC3T-02 is a compact torch height controller for CNC plasma cutting, with a built-in 1:50 voltage divider so it works with plasma cutters that have no divided arc voltage output. It reads the arc voltage while the torch is cutting and automatically raises or lowers the torch to keep a constant distance to the plate, so cut quality stays consistent even when the sheet is warped or the cutting bed is not perfectly flat. Signal-processing algorithms stabilize the voltage reading, and a smooth-motion algorithm prevents jerky Z movement. Connection is as simple as it gets: just three outputs – UP, DOWN and ARC OK – wired to your CNC controller, which then moves the Z axis. It detects ARC OK automatically, self-calibrates to the arc voltage of your plasma cutter, and integrates with Mach3 software. Designed and built by Robot3T in Vietnam.
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- CNC plasma cutting tables: gantry and table machines running Mach3.
- Warped or uneven sheet: keeps torch height constant over bends and waves.
- Machine builders: a compact, cost-effective THC for new plasma machines.
- Retrofits: adding automatic height control to existing machines.
Why THC3T-02
- Better cut quality – constant torch height means consistent kerf, bevel and less dross.
- Longer consumable life – avoids torch dives and crashes caused by uneven plates.
- Simple wiring – only three outputs: UP, DOWN and ARC OK; ideal for retrofitting existing machines.
- No extra divider needed – integrated 1:50 divider takes the raw arc voltage directly.
- Stable reading – signal processing filters arc voltage noise; smooth-motion algorithm for gentle Z moves.
- Easy setup – automatic ARC OK detection and arc voltage calibration; adjust height on the fly with a potentiometer.
- Convenient – jog the Z axis from software in idle mode.
Specifications
| Model | THC3T-02 (Up/Down, integrated divider) |
| Plasma source | Any plasma cutter; auto-calibrates arc voltage |
| Voltage divider | Integrated 1:50, with noise filtering |
| Height sensing | Arc voltage, with signal-processing filter |
| Outputs | UP, DOWN, ARC OK to CNC controller |
| ARC OK | Automatic detection |
| Height adjustment | Online, by potentiometer |
| Idle mode | Z jog from software |
| CNC software | Mach3 |
| Origin | Robot3T, Vietnam |
Product, diagrams and setup
Up/Down or Step/Dir?
| Feature | Up/Down | Step/Dir |
|---|---|---|
| Output to machine | UP, DOWN, ARC OK signals to the CNC | Step/Dir directly to the Z driver |
| Wiring | Simplest – 3 outputs | Connects between CNC and Z driver |
| Z response | Through the CNC controller | Direct – faster and more precise |
| Best for | Easy retrofits, standard Mach3 THC setup | Highest performance on new machines |
Both versions: arc voltage sensing, auto ARC OK, auto calibration, smooth motion, Mach3 integration.
Documentation
Download user manual (Up/Down)See it in action
Constant torch height, clean cuts
- Arc voltage keeps the torch at the right height.
- Simple UP / DOWN / ARC OK wiring.
- Works with Mach3 out of the box.
Frequently asked questions
How is this different from the Hypertherm version?
This version has the 1:50 voltage divider and noise filter built in, so it reads the raw arc voltage directly from plasma cutters without a divided output. The Hypertherm version uses the divided signal provided by Hypertherm sources. Tell us your plasma model and we will recommend the right one.
Can I use it with software other than Mach3?
This Up/Down version is made for Mach3. For other CNC software or controllers, contact us and we will recommend a suitable THC version.
Up/Down or Step/Dir – which should I choose?
Choose Up/Down for the simplest wiring and easy retrofits. Choose the Step/Dir version when you want the THC to drive the Z motor directly for the fastest response.
Do you ship outside Vietnam?
Yes. Contact sales@robot3t.com for a quote including shipping to your country.
Want cleaner plasma cuts?
Tell us your plasma source, CNC software and machine. Our engineers will recommend the right height controller and accessories, and quote at no cost.
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