Start-circuit pcb1, Operation, Start circuit functional schematic – Hypertherm HPR800XD Auto Gas Rev.2 User Manual
Page 255: Start circuit troubleshooting, Start-circuit pcb1 -41, Danger
Maintenance
HPR800XD Auto Gas –
806500
5-41
Start circuit functional schematic
Start circuit troubleshooting
Start-circuit Pcb1
operation
The start circuit is a high-speed switch that quickly transfers the pilot arc current from the pilot arc lead to the work lead.
The start circuit performs 2 functions:
1. It allows the initial pilot arc current to flow through the pilot arc lead quickly, with little impedance.
2. After initial pilot arc current is established, the start circuit introduces impedance to the pilot arc lead to aid in
transferring the arc to the workpiece. See schematic below.
Plasma power supply
Choke
Diode
Start circuit
cutting
arc
Pilot
arc
Power
resistor
Control
logic
ALEL Caps
chopper
IGBT
DANgER
SHock HAzARD
Always use caution when servicing a power supply when plugged in and the covers are removed.
Dangerous voltages exist within the power supply which could cause injury or death.