ESAB LAW 400 User Manual

0740 800 025 9708
LAW 400/500
LAW 410/510
Welding rectifier
Service manual

ESAB LAW 400 Specifications

General

Brand	ESAB
Model	LAW 400
Category	Welding System
Language	English

Summary

Read This First

Safety Warnings

Crucial safety precautions for arc welding and operating the unit.

Component Description

Connection Diagram, LAW 400/500 400-415 V

Connection Diagram, LAW 400/500 230-500 V

Connection Diagram, LAW; 400-415 V (from machine no. 512)

Connection Diagram, LAW; 230-500 V (from machine no. 512)

Function Description

Power Supply Circuit Board AP1

Details the power supply circuit board AP1 and its DC voltage outputs.

DC Power Supplies

Power Supply Voltages (+12V, +15VB, +/-15V, +25VC)

Fixed / Controlled Firing Angle

Explains jumper settings for fixed or controlled thyristor firing angle.

Thermal Overload Cutout

Explains operation of thermal overload cutout ST1 and LED V7.

Arc Voltage (Serial Nos. 434)

Arc Voltage (Serial Nos. 512+)

Shunt Input

Explains shunt RS1 signal and its connection to the processor.

Crater Filling

Thyristor Circuits

Details thyristor firing circuits using operational amplifiers and checking procedures.

Processor Functions

Lists processor functions like frequency measurement, overload protection, and hot start.

Elevated Starting Voltage (Hot Start)

Explains hot start feature for different machine serial numbers and circuit boards.

Presetting

Pulse Welding

Test Routine

Technical Data

Primary Connections LAW; 230 - 500 V

Control Panel and Connections

Spare Parts List LAW 400/500

Spare Parts List LAW 410/510