OPERATION
CommandTHC for X-Y Table
Instruction Manual
4-15
11
1.
CNC traverses to next piercing position.
2.
For multiple torch /THC installations only: CNC issues INS-SYNC-IN signal to each THC.
This signal holds arc firing until all THCs are at IHS position.
3.
CNC issues a CYCLE-START-IN to THC.
4.
If Preflow During IHS is enabled, THC issues a PLASMA-START-OUT and a HOLD-IGNITION-OUT
signal to plasma power supply.
5a. If Nozzle Contact (ohmic contact) is enabled, torch approaches plate at programmed speed and stall
force until nozzle makes ohmic contact with plate; then retracts slowly until nozzle ohmic contact is lost
and then retracts to pierce height.
or
5b. If Nozzle Contact (ohmic contact) is disabled, torch dives at programmed speed and stall force, until a
motor stall is detected and then retracts to pierce height
6.
For multiple torch /THC installations only: THC issues IHS-COMPLETE-OUT signal to CNC. When all
IHS-COMPLETE-OUT signals have been satisfied, CNC releases IHS-SYNC-IN signal.
7.
If Preflow During IHS is not enabled, THC issues a PLASMA-START-OUT signal to plasma power supply.
8.
If Preflow During IHS is enabled, THC releases arc HOLD-IGNITION-OUT signal.
9.
Preflow completes, if it has not already completed.
10.
Torch ignites.
11.
Arc transfers to workpiece. Plasma power supply issues ARC-TRANSFER-IN to THC.
12.
Programmed pierce delay signal elapses.
13.
Torch quickly dives from pierce height to programmed cut height; programmed MACHINE ACCEL
DELAY begins; THC issues PIERCE-COMPLETE-OUT signal to plasma power supply; and THC issues
MACHINE-MOTION-OUT signal to CNC to begin profiling part.
14.
After MACHINE ACCEL DELAY elapses, arc voltage control (AVC) begins. During AVC, an AUTO-
HEIGHT-ON/OFF from CNC freezes torch position (traditional CORNER HOLD). During AVC, CNC
should issue an AUTO-HEIGHT-OFF when CNC not moving at programmed velocity. During AVC, if
AUTO KERF DETECT is enabled, torch position is frozen when crossing kerfs.
15.
At end of cut, CNC releases CYCLE-START-IN signal to THC. Programmed retract delay begins.
16.
Programmed retract delay time elapses and the THC raises torch until home limit switch is reached or
partial retract height is checked.
17.
THC issues RETRACT-COMPLETE-OUT signal to CNC allowing traverse to next cut position
.
Automatic mode time-line
Start
Cycle completed, return to Start for next cycle.
