Plasma Digital Torch Height Controller

A microprocessor controlled DTHC specifically designed to work exclusively with selected models from the Hypertherm Powermax range of plasma cutters and where your table is controlled by Mach3.

Please read carefully to see if this THC is suitable for your system.

Other aftermarket THC systems need either interface electronics or the whole system to be installed inside the plasma cutter power supply. However, most Hypertherm models come with an interface already built in as standard. (Hypertherm refer to this variously as the robotics interface, the mechanized cutting interface or the machine interface). The Razordance THC is exclusively designed to connect to that existing interface so you don't need to install anything inside the plasma cutter power supply case. If you have one of these Hypertherm models then this THC is the one for you.

So which models are supported?

The simple answer is - any model that has an interface built in with a 50:1 voltage divider. Hypertherm seem to change models now and then but at the time of writing, the current models of the Powermax45, Powermax1000, 1250 and 1650 have the interface as standard with a plug brought out on the rear panel.

However, note that there are some early models of the Powermax1000, 1250 and 1650 that were not equipped with the divided (50:1) output. These earlier units would not have connections on pins 5 and 6 of the interface connector. I am told there is a Hypertherm upgrade part for this (Hypertherm part# 123892) but you should contact your Hypertherm dealer to confirm that yours can be upgraded.

The newer Powermax65 and 85 are shipped with the interface as an option. If yours doesn't have it you can upgrade with the addition of Hypertherm part# 228696.

I have absolutely no affiliation with Hypertherm so there may be other plasma cutter models or options that they sell that have a similar interface. If in any doubt I suggest you contact your dealer and simply ask whether your system has the same robotics interface as the Powermax45.

The above plasma systems all come with the option of having a hand held torch or a machine torch. To use this THC you MUST have the machine torch. This is because for safety reasons, Hypertherm disable their robotics interface when the hand torch is connected.

What else is needed in order to use this THC?

  • A Machine Interface Cable with a D-sub Connector that includes the wires for the Voltage Divider Signal. If you don't already have one of these then they can be purchased from your local Hypertherm dealer. (Ask for part# 123896)
  • A CNC table controlled by a licenced[1] Mach3 (VR3.043.022 or later) via the parallel port or one of the external motion control cards that FULLY support THC functionality.[2]
  • Some method of performing Initial Height Sensing (IHS). Floating head and/or Ohmic sensing are two popular methods. You should be doing this anyway even if you don't yet use a THC.
  • 1 spare SERIAL (RS232) port on your PC or USB with a USB to RS232 Converter Cable.
  • 1 spare output pin on your parallel port/BOB.
  • 3 spare input pins on your parallel port/BOB.
  • Note that you don't need a second parallel port to use this THC.
  • A REGULATED 5Vdc supply - what you use for the logic supply of your motor drivers is fine.

[1] Mach3's internal THC functionality is crippled in demo mode.

[2] These days, any decent external controller should fully support THC. Examples, to the best of my knowledge, include the ESS (Ethernet SmoothStepper), The uc100 and 300 and CSMIO. However note that user supplied 24V to 5V level shifting is required to interface the CSMIO.

What do I get if I buy the THC?

  • The THC card itself of course, which measures approx. 100mm x 90mm (4" x 3.5").
  • A 1.8 Metre DB9 male to female RS232 Serial Extension Cable.
  • A custom Mach3 plasma Screenset with associated setup and control files.
  • Comprehensive and easy to follow hardware and software installation instructions.


Digital Torch Height Controller

Mach3 Screenset

Custom Mach3 THC Screenset

How do I operate the THC?

  • Set the required voltage for your job. You can do this either in the Mach3 screen DRO, set it in gcode with the S word or use the "Sample & Hold" feature.
  • Switch on Mach3's THC control via the on-screen button.
  • Optionally, switch on Mach3's anti-dive control via the on-screen button.
  • Run your job.
  • If neccessary, you can fine adjust the required arc voltage on-screen in real time whilst your job is running.
  • The actual arc voltage is displayed real-time throughout the cutting process. This makes tweaking your optimum arc voltage and hence your optimum torch to work height a snip.
  • Once you've tweaked your system you can pretty much enter your required voltage or even better put it in your g-code and forget it, the THC will keep your optimum cut height without further intervention. No knobs to twiddle or madly flickering LCD displays to try to chase.

The Razordance Digital Torch Height Controller costs £190 (GBP). This price includes FREE shipping worldwide.

Shipping normally takes from 1 to 3 working days within the EEC and a week or so elsewhere. However some countries seem to have slower than average customs clearance so depending on your location it may take a few days longer.

Razordance working hours are 09:00 to 17:00 GMT Monday to Friday. Orders placed at the weekend will be shipped on Monday.

Please note:

  • Any local import taxes or duties are your responsibility to pay.
  • The item must be signed for on delivery.
  • Please read the Terms & Conditions of Sale before you buy. (If you don't have a PDF reader I suggest Foxit PDF reader)
  • Please check your PayPal email address from time to time for shipping updates.

Payment is via PayPal. If you don't have a PayPal account you can pay with your debit or credit card as a PayPal guest. Just click Buy Now and follow the instructions.


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