How To Use Troubleshooting Guide - Lincoln Electric PRESTO 275 Service Manual

HOW TO USE TROUBLESHOOTING GUIDE

Service and repair should be performed by only Lincoln Electric Factory Trained Personnel.
Unauthorized repairs performed on this equipment may result in danger to the technician and machine
operator and will invalidate your factory warranty. For your safety and to avoid Electrical Shock, please
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This Troubleshooting Guide is provided to help
you locate and repair possible machine
malfunctions. Simply follow the three-step
procedure listed below.
Step 1. LOCATE PROBLEM (SYMPTOM). Look
under the column labeled "PROBLEMS".
This column describes possible
symptoms that the machine may exhibit. Find
the listing that best describes the symptom that
the machine is exhibiting. Symptoms are
grouped into three main categories: Output
Problems, Function Problems, and LED Function
Problems.
Step 2. PERFORM EXTERNAL TESTS. The
second column, labeled "CHECKS", lists the obvious
external possibilities that may contribute to the
machine symptom. Perform these tests/checks in the
order listed. In general, these tests can be
conducted without removing the case
wrap-around cover.
observe all safety notes and precautions detailed throughout this manual.
Step 3. PERFORM COMPONENT TESTS. The
last column, labeled "RECOMMENDED COURSE OF
ACTION " lists the most likely components that may
have failed in your machine. It also specifies the
appropriate test procedure to verify that the
subject component is either good or bad. If there
are a number of possible components, check the
components in the order listed to eliminate one
possibility at a time until you locate the cause of
your problem.
All of the referenced test procedures referred to in
the Troubleshooting Guide are described in detail
at the end of this chapter. Refer to the
Troubleshooting and Repair Table of Contents to
locate each specific Test Procedure. All of the
referred to test points, components, terminal
strips, etc., can be found on the referenced
electrical wiring diagrams and schematics. Refer
to the Wiring Diagrams Section Table of
Contents to locate the appropriate diagram.