Hypertherm HPR130, Instruction Manual

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MAINTENANCE
HPR130 Manual Gas Instruction Manual 5-5
5
Sequence of operation
1. Power-up – The system verifies that all of these signals are off at power-up
Coolant flow off
Chopper current off
Transfer off
Phase Loss off
Chopper 1 over-temp off
Magnetics over-temp off
Coolant over-temp off
Plasma start off
2. Purge – Air or N
2
gas flows through torch for 20 seconds
Coolant flow on
Contactor closes and the chopper performs a chopper test and a current sensor test
Plasma start off
Contactor opens when the purge cycle ends
3. Idle
Gas pressure ok
Coolant flow on
Chopper current off
Line voltage ok
4. Preflow – 2 second flow of gas
5. Pilot Arc – Current flow between electrode and nozzle
Chopper, main contactor and pilot arc relay are on
High frequency present
Chopper current sensor = pilot arc current
6. Transfer – Pilot arc current sensed on the worklead
7. Ramp-up – Chopper current increases to set point and gas switches to cutflow
Coolant flow on
Gas pressure ok
Phase loss on
Line voltage ok
8. Steady State – normal operating parameters
Coolant flow on
Gas pressure ok
Phase loss on
Chopper 1 over-temp off
Magnetics over-temp off
Coolant over-temp off
9. Ramp-down – Current and gas flow decreases after plasma start has been removed
Cutflow gas off
10. Auto Off – 10 second postflow
Main contactors off
Choppers off