diff --git a/docs/source/developers.rst b/docs/source/developers.rst index 27b065460aff..d8c3cbcb453a 100644 --- a/docs/source/developers.rst +++ b/docs/source/developers.rst @@ -21,7 +21,12 @@ To be continued... THC *** -ToDo +THC stands Torch Height Control. To achieve optimal cutting with plasma, it is important to keep the torch tip-to-plate distance constant at about 0.06" (1.5mm). +The voltage and the distance between torch tip and plate / cutting material being directly proportional, THC is a feedback loop controlling the height of the plasma torch, maintaing a constant distance to the material. +Typically, a plasma cutter operates within 60 to 150V DC. Some CNC-able plasma cutters have a CNC port outputting a ratio of operating voltage. This is done usually with a resistor divider. For example a given model has an operating voltage of max voltage of 125V DC, and a 50:1 resistor divider outputs 2.5VDC maximum. + +Klipper plasma can measure in real-time this voltage to constantly adjust the height of the torch and follow the surface of the material. Thin material can warp, even thick material can be bent or uneven, the THC feature compensates for this. + JIT input *********