OS3T-01 Ohmic Sensor for CNC Plasma Cutting
$36.00
Ohmic sensor for CNC plasma cutting: detects contact between torch shield and plate for accurate initial height sensing. Survives HF and HV sparks up to 660 VDC, 0–1 MΩ sensing range, adjustable sensitivity, isolated PNP output, 12–24 VDC with reverse-voltage protection. Made in Vietnam by Robot3T.
OS3T-01 is an ohmic sensor that lets your CNC plasma cutter find the plate surface accurately before every pierce. It detects the electrical contact between the torch shield and the metal plate, so the machine knows the exact initial height without pressing on the material – faster and more precise than mechanical touch-off on thin or flexible sheet. Built for the harsh plasma environment, it withstands high-frequency and high-voltage starting sparks up to 660 VDC, and its isolated PNP output connects safely to the CNC controller. Sensitivity is adjustable to suit dirty, coated or oily plates. Designed and built by Robot3T in Vietnam.
Request a quote WhatsApp +84 974 908 615Typical applications
- Initial height sensing (IHS): accurate pierce height on every cut for CNC plasma tables.
- Thin and flexible sheet: touch-off without bending the plate.
- Torch height control systems: works together with THC3T-02 controllers.
- Machine builders and retrofits: adding ohmic sensing to new or existing plasma machines.
Why OS3T-01
- Built for plasma – survives HF and HV starting sparks, arc voltage input up to 660 VDC.
- Accurate and fast – electrical contact sensing finds the plate surface without mechanical force.
- Safe connection – isolated PNP output protects the CNC controller.
- Adjustable sensitivity – reliable on clean, rusty, coated or oily plates.
- Long life – output relay rated for at least 108 operations at 24 V / 16 mA.
- Robust power input – 12–24 VDC with built-in reverse-voltage protection.
Specifications
| Model | OS3T-01 |
| Power supply | 12–24 VDC, 0.1 A |
| Reverse voltage protection | Integrated |
| Sensing range | 0–1 MΩ |
| Sensitivity | Adjustable |
| Output | Isolated PNP |
| Relay life | ≥ 108 operations (24 V / 16 mA) |
| HV / HF protection | Arc voltage input up to 660 VDC, HF ionizing voltage |
| Origin | Robot3T, Vietnam |
Product and wiring
Documentation
Download user manualSee it in action
Ohmic touch-off before every pierce
- Torch shield touches the plate – signal sent instantly.
- Correct pierce height, longer consumable life.
- Reliable despite plasma HF and HV sparks.
Frequently asked questions
Do I need an ohmic sensor if I have a THC?
Yes, they do different jobs. The ohmic sensor sets the correct initial height before piercing; the THC keeps the height constant while cutting. Together they give the best cut quality.
Does it work with any CNC controller?
Its isolated PNP output connects to the probe or input of most CNC controllers and software such as Mach3. Tell us your system and we will confirm the wiring.
What if my torch has no ohmic shield connection?
Contact us with your torch model; we will advise on wiring or an alternative such as a mechanical float switch.
Do you ship outside Vietnam?
Yes. Contact sales@robot3t.com for a quote including shipping to your country.
Want accurate pierce height on every cut?
Tell us your plasma source, torch and CNC controller. Our engineers will recommend the right sensor and height control set, and quote at no cost.
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