Please read carefully to see if this DTHC 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 DTHC 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 DTHC is the one for you.
So which models are supported?
Hypertherm are constantly bringing out new models but the simple answer is - any model that has an interface built in with a 50:1 voltage divider. If in any doubt I suggest you contact your dealer and simply ask whether your system has the same robotics interface as the Powermax45. If it does then all is well. If it doesn't, ask if there's an update pack for your model.
Please note that to use this DTHC you must have the machine torch. This is because for safety reasons, Hypertherm disable their robotics interface when the hand torch is connected.
Note as of 2016:
Manufacturers other than Hypertherm are now producing plasma cutters with built in interfaces. If the interface is the same, then this DTHC will work fine with them.
What else is needed in order to use this DTHC?
- 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 Mach3 (VR3.043.022 or later) via the parallel port or one of the external motion control cards that FULLY support THC functionality.
- 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.
- A USB port with a USB to RS232 Converter Cable. (OR on older PCs you can use a spare SERIAL (RS232) port and a straight-through RS232 extension 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 DTHC.
- A REGULATED 5Vdc supply - what you use for the logic supply of your motor drivers is fine.
 Mach3's internal THC functionality is crippled in demo mode.
 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.
 I used to bundle an RS232 extension cable with the THC. However as more people are using USB to RS232 cables these days they were more often than not, not being used. I therefore don't ship these cables anymore. They're readily and cheaply available on-line if you decide to use one rather than USB to RS232.
What is the sample rate of the Razordance DTHC?
1KHz or 1000 times per second. I mention this here because there is a myth repeated from time to time on the Mach3 forum that Mach3 can only handle THC updates at 10Hz i.e. ten times per second. This is completely untrue and comes (I believe) from confusing input speed with either the macropump refresh rate or the screen update period. Neither of which have anything to do with Mach3's THC functionality.
What do I get if I buy the DTHC?
- The DTHC card itself of course, which measures approx. 100mm x 90mm (4" x 3.5").
- A custom Mach3 plasma Screenset with associated setup and control files.
- Comprehensive and easy to follow hardware and software installation instructions.