An automatic Torch Height Controller is an essential part for CNC plasma machines. The THC monitors the arc voltage from the plasma cutter and uses this information to control the position of the torch relative to the material being cut. It will precisely maintain the correct height over the work area to create the best possible cut. The THC also allows the user to determine pierce height and pierce delay, extending the life of torch consumables.
The Proma THC 150 is a popular controller of the plasma torch’s height with relay outputs Up/Down and ARC OK – confirmation of the cutting arc. It is intended to cooperate with CNC control systems which support THC signals up/down, for example Mach3, Linux CNC. The integration of a voltage divider makes installation quite simple.
- Supply voltage (V)7-35V DC
- Works with any plasma cutter Input voltage 20-300V DC
- Ability of HV/HF ionization voltage suppressing 30kV
- Ability of HV/HF ionization frequency suppressing >11kHz
- Duty cycle (%) 100%
- Duty cycle of HV/HF suppression (%) 100%
- Rated max. load 1.25A/60V DC
- Relay reliability (min. amount of cycles) under load of 5V/10mA: 500*10^6
- Degree of protection of enclosure IP IP20
- Easy to install
When connecting directly to the “power” terminals, keep the connection as short as possible to avoid high noise levels
You should also use test leads with appropriate insulation – matched to the maximum voltage of the plasma cutter. Due to the very high level of interference and voltage “pins”, it is recommended to connect the + and – potential with separate wires, which minimizes the risk of insulation breakdown.
An exemplary MACH3 configuration: