KERFCROSS(9) HAL Component KERFCROSS(9) NAME kerfcross - Plasma THC Helper Application to detect kerf crossing SYNOPSIS loadrt kerfcross [count=N|names=name1[,name2...]] DESCRIPTION When a plasma cutter crosses a kerf, there is a sharp increase in torch volts. A THC will try to compensate for this by lowering the torch. This can result in a torch crash. This component monitors the torch voltage and if the rate of change exceeds a threshold (in volts per period), the output from this component can be used to disable a THC for a set number of periods. Suggested values are a threshold of 1 volt change per 2 periods fol‐ lowed by a lockout of 10 periods. To simplify the calculations, the lockout period and sample period are defined by the number of servo threads that pass. The default servo thread timing is 1 millisecond. EXAMPLE: This example ORs the Cornerlock enable signal hold with the Kerf Cross enable signal and sends to e-offset_pid hold and also shares the Gmoc‐ capy Corner lock enable pin so the GUI chjeckbox enables both kerf crossing and corner lock. loadrt kerfcross.comp names=k-cross loadrt eoffset_pid names=zo loadrt or2 count=1 addf k-cross servo-thread addf zo servo-thread 1 addf or2.0 servo-thread setp k-cross.threshold 1 setp k-cross.cycle-count 2 setp k-cross.lockout-periods 10 net E:command <= k-cross.torch-volts net kc-enabled <= k-cross.enabled net kc-enabled => or2.4.in0 net CL-HeightLock => or2.4.in1 net E:hold-active or2.4.out => zo.hold-request FUNCTIONS kerfcross.N (requires a floating-point thread) PINS kerfcross.N.torch-volts float in Live torch Volts kerfcross.N.threshold float in (default: 1) Threshold change in torch volts (Volts per cycle_count period) kerfcross.N.cycle-count u32 in (default: 2) Number of cycles between samples kerfcross.N.enabled bit in (default: 1) Set to TRUE to enable kerf crossing detection kerfcross.N.active bit out True if torch volts exceeds the threshold change, connect to THC disable pin kerfcross.N.lockout-periods u32 in (default: 10) Number of cycles to lock out THC AUTHOR Rod Webster LICENSE GPL LinuxCNC Documentation 2017-04-23 KERFCROSS(9)