Board reference

LGK100L Control Board Connector Reference

A board-level reference for LGK100L control-board inputs, outputs and protection evidence.

Quick Answer

The LGK100L control board is a high-value reference because it combines AC8V input, control transformer secondary input, Hall sensor/current sensor, overcurrent and temperature indicators, pressure switch, potentiometer, drive output, HF control and gas valve control.

Use this reference to avoid replacing the control board before checking external connector evidence.
Protection light diagnostics should split temperature relay, Hall sensor, transformer rails and pressure switch paths.
No-output diagnostics should split command, drive output, Hall feedback and downstream power-board evidence.

Use this page when

You are diagnosing LGK100L protection, no output, display, pressure, gas or HF-control symptoms.
Connector evidence such as X13, X7, X14 or related control-board paths can be checked.
You need to map a symptom to a control-board input/output.

Do not use this page when

The input rectifier or IGBT is visibly shorted.
The machine is completely dead before control supply appears.
You only need front-panel part identification.

Service map

LGK100L control-board connector map

Connector evidence grouped by function rather than physical position.

AC8V / transformer input

Low-voltage supply layer for display/control behavior.

Temperature relay

Thermal-protection evidence before control-board replacement.

Hall / current sensor

Current-feedback layer for protection and no-output diagnosis.

Pressure switch

Air-pressure safety input for plasma cutting.

Drive signal output

Control-board output toward driver/power stage.

HF / gas control

Start-control layer for arc-start and solenoid behavior.

Connector evidence and related faults

Connector / signal group	Related symptom	Service direction
X13 DC5V display supply	Display missing while fan runs	If DC5V exists at X13 1# and 2#, display or board decision path is implicated.
X7 rail group	Protection light, no output	Check 0-27V-36V and 15V-0-15V rail evidence before board replacement.
X14 Hall sensor group	Protection light, no output, current small	Check DC15V, -DC15V and signal behavior before replacing Hall sensor or main board.
Temperature relay input	Power-on protection light	Unplug test can separate thermal relay from board decision.
Pressure switch	No cutting start or protection behavior	Confirm pressure switch state and wiring.
Drive signal output	No output after normal control inputs	Move toward driver board, IGBT and output power stage.

Next diagnostic step

LGK100L protection lightUse temperature/Hall/rail split.LGK100L no outputUse control and power-stage split.Hall current sensorConfirm current-feedback evidence.