Circuit reference

LGK Plasma Cutter Control Power Rails

A practical low-voltage rail reference connecting LGK60L and LGK100L fan, protection, display, feedback and no-output faults.

Quick Answer

LGK plasma-cutter control-power diagnosis should separate AC control-transformer rails from DC24V board outputs and sensor feedback supplies. This reference connects LGK60L and LGK100L evidence points.

LGK60L uses X17 AC15V-0V-15V evidence and X16 DC24V fan-output evidence.
LGK100L workflows include 0-27V-36V / 15V-0-15V rail groups and DC15V/-DC15V Hall sensor supply evidence.
Low-voltage rail faults can look like fan, display, protection, no-output or feedback faults.

Use this page when

You are diagnosing fan, display, protection, feedback or no-output faults in LGK plasma cutters.
The machine can be measured safely by a qualified technician.
You need to compare AC rails, DC outputs and feedback supplies.

Do not use this page when

The input breaker trips immediately before low-voltage checks.
The power stage is visibly shorted.
You only need torch consumable advice.

Service map

LGK control-power rail map

Low-voltage evidence used before replacing boards.

AC15V-0V-15V

LGK60L X17 and related control-transformer secondary evidence.

DC24V output

Fan and control output evidence such as LGK60L X16.

0-27V-36V group

LGK100L connector rail evidence used in protection/no-output workflows.

DC15V / -DC15V

Hall current-sensor supply evidence for feedback diagnosis.

DC5V display supply

Display/meter supply layer on larger platforms.

Control-power rail evidence

Rail / connector evidence	Fault it can explain	Next direction
LGK60L X17 AC15V-0V-15V	Fan/control abnormal; main board appears dead	Check control transformer and wiring.
LGK60L X16 DC24V	Fan not running	If missing with fan disconnected, suspect main control board output.
LGK100L 0-27V-36V / 15V-0-15V group	Protection light or no output	Check control transformer before replacing control board.
LGK100L X14 DC15V / -DC15V	Hall sensor/protection/no-output faults	Check Hall sensor and feedback wiring.
DC5V meter/display supply	Display missing with fan running	Separate display head from control board/power board.

Next diagnostic step

LGK60L fan not runningUse X16 and X17 evidence.LGK100L protection lightUse rail and Hall sensor split.Hall current sensorUse current-feedback rail evidence.