ESAB LAW 400, Service Manual

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claw0de1
READ THIS FIRST
This service manual is intended for use by technicians with electrical/electronic training, for
help in connection with fault--tracing and/or repair.
Use the connection diagram as a form of index for the description of operation and the
component description. The circuit board is divided into numbered blocks, which are
described individually in more detail in the description of operation. All component names in
the connection diagram are listed in the component description.
This manual contains details of all design changes that have been made up to and including
August 1997.
The LAW 400/500 and 410/510 are designed and tested in accordance with interna-
tional standard
EN 60 974--1 (IEC 974--1).
On completion of any service or repair, it is the responsibility of the person or
organisation performing the service to ensure that the product still complies with the
above standard.
WARNING
READ AND UNDERSTAND THE INSTRUCTION MANUAL BEFORE INSTALLING OR OPERATING.
ARC WELDING AND CUTTING CAN BE INJURIOUS TO YOURSELF AND OTHERS. TAKE PRECAU-
TIONS WHEN WELDING. ASK FOR YOUR EMPLOYER’S SAFETY PRACTICES WHICH SHOULD BE
BASED ON MANUFACTURERS’ HAZARD DATA.
ELECTRIC SHOCK -- Can kill
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Install and earth the welding unit in accordance with applicable standards.
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Do not touch live electrical parts or electrodes with bare skin, wet gloves or wet clothing.
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Insulate yourself from earth and the workpiece.
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Ensure your working stance is safe.
FUMES AND GASES -- Can be dangerous to health
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Keep your head out of the fumes.
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Use ventilation, extraction at the arc, or both, to keep fumes and gases from your breathing zone and
the general area.
ARC RAYS -- Can injure eyes and burn skin.
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Protect your eyes and body. Use the correct welding screen and filter lens and wear protective
clothing.
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Protect bystanders with suitable screens or curtains.
FIRE HAZARD
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Sparks (spatter) can cause fire. Make sure therefore that there are no inflammable materials nearby.
NOISE -- Excessive noise can damage hearing
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Protect your ears. Use ear defenders or other hearing protection.
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Warn bystanders of the risk.
MALFUNCTION -- Call for expert assistance in the event of malfunction.
PROTECT YOURSELF AND OTHERS!