Problems And Solutions - Hypertherm Command THC Instruction Manual

OPERATION
Table 4-1
Problem
No response to CYCLE-START-IN at THC.
Arc ignites before IHS is complete.
Torch does not approach workpiece at
programmed IHS speed and stall force.
Inaccurate IHS with nozzle ohmic contact.
Inaccurate IHS with Stall Force sensing
Torch fails to ignite.
4-16
11
THC operating cycle (automatic mode) process problems and solutions
(Refer to operating cycle time-line on previous page)
Solution
• Check power to THC. On THC control PCB, D41 – D44 should be
illuminated.
Check line input fuses in THC power module.
• Check for bad Cycle Start connection. Check on THC control PCB,
Machine Interface Inputs, that D9 is illuminated.
• Check on control PCB, Machine Interface Inputs, that D15 is
illuminated.
• Check on control PCB, External Interlock OK, that D16 is illuminated.
• Check that Maintenance Mode is not selected on pendant or do
query on RS-422.
• Check that Preflow During IHS is OFF (disabled) on Setup Screen A.
• If plasma power supply has a Hold signal, check that it is wired properly.
• Check that THC is in Automatic Mode. If not, press <AUTO/MAN>
key on keypad.
• Check that Stall Force is not set too low on Setup Screen A.
• Check that IHS Speed is not set too high on Setup Screen A.
• Check for cable and hose obstructions that may stop movement.
• Check that THC is in Automatic Mode. If not, press <AUTO/MAN>
key on keypad to select Automatic Mode.
• Check that Nozzle Ohmic Contact is ON (enabled) on
Setup Screen A.
• Check that nozzle ohmic contact wire is not disconnected. Ensure wire
is connected at both ends.
• Check Pierce Height Factor on Setup Screen A.
• Check that torch retaining cap is tight.
• Check for water on the workpiece. If present, use Stall Force sensing.
Refer to 5b on previous page.
• Check for coating (oil, plastic, etc.) on the workpiece. If present, use
Stall Force sensing. Refer to 5b on previous page.
• Check nozzle/shield, clean or replace.
• Check work lead connection.
• Check that Nozzle Ohmic Contact is OFF (disabled) on
Setup Screen A.
• Check Pierce Height Factor on Setup Screen A.
• Check that Stall Force is not set too high on Setup Screen A.
• Check that workpiece is not deflecting excessively. Check the work
table supports under the workpiece.
• Offset workpiece deflection by adjusting Set Cut Height on Automatic
Operating Screen and Pierce Height Factor on Setup Screen A to
achieve desired results.
• Ensure plasma system is operational.
• Check for proper IHS piercing height. Check torch.
• Check that IHS SYNC is off. Check on THC control PCB, Plasma
Interface Inputs, that D13 is extinguished.
• Check torch consumables.
CommandTHC for X-Y Table Instruction Manual