Boards
Circuit Board Index
Board-level index for control modules, auxiliary power boards, driver boards, wire-feed boards and HF arc-start boards.
Records
- ZX7-400 full-bridge MOSFET inverter board — Explains DC bus, bridge switch groups, blocking capacitors, main transformer and secondary output path.
- SG3525 control modules — SG3525 control modules are common in ZX7-style inverter welders and are important for no-PWM and shutdown diagnosis.
- UC3846 control boards — UC3846 control boards are important for current-mode PWM, peak current feedback, shutdown and no-output diagnosis.
- KA3843 / KA3845 auxiliary power boards — Auxiliary power boards generate 24V, 15V, 12V and 5V rails used by control and driver circuits.
- Long-strip control boards — Long-strip control boards often combine auxiliary power, drive interfaces, feedback and shutdown paths in ZX7 welders.
- MOSFET / IGBT driver boards — Driver boards translate PWM control into isolated gate-drive signals for MOSFET or IGBT power stages.
- Wire feeder boards — Wire feeder boards control MIG wire-feed motors, trigger input, gas valve logic, 2T/4T and braking.
- HF arc-start boards — HF arc-start boards are used in TIG welders and plasma cutters for high-frequency ignition and pilot arc starting.
- Dual-voltage switching boards — Dual-voltage boards detect 220V/380V input conditions and control boost/doubler or relay switching.
- ZX7-250 IGBT driver and control power board — ±25V, 7815, 7805, 7915 and driver-suspicion logic.
How to use this section
Board pages explain function, input signals, output signals, likely failure modes and related repair cases.