Tweco PC-800 - Manual (Page 37)

Manual 0-4603 5-5 SERVICE
5.03 Basic Troubleshooting Guide
WARNING
There are extremely dangerous voltage and power levels present inside this unit. Do not attempt to diagnose or repair
unless you have had training in power electronics measurement and troubleshooting techniques.
A. Basic Troubleshooting: Overview
This guide covers basic troubleshooting. It is helpful for solving many of the common problems that can arise with this
system. If major complex subassemblies are faulty, the unit must be returned to an authorized service center for repair.
Follow all instructions as listed and complete each section in the order presented.
For major troubleshooting and parts replacement procedures refer to the Power Supply Service Manual for this prod-
uct.
B. How to Use This Guide
The following information will help the Customer / Operator determine the most likely causes for various symptoms.
Follow all instructions as listed and complete each section in the order presented.
This guide is set up in the following manner:
X. Symptom (Bold Type)
Any Special Instructions
1. Cause
a. Check / Remedy
Locate your symptom, check the causes (easiest listed first), then remedies. Repair as needed being sure to verify that
unit operates properly after any repairs.
C. Common Symptoms
A. AC indicator OFF
1. Switch at main power panel in OFF (open) position.
a. Close main power switch.
2. Power Supply ON / OFF switch in OFF (down) position.
a. Turn switch to ON (up).
3. Torch is not connected properly to Power Supply
a. Turn power supply ON / OFF switch to OFF (down). Check torch connection to Power Supply. Tighten or
adjust as required. Do not use tools. Turn power supply ON / OFF switch to ON (up).
4. Shield cup not fully tightened on torch head
a. Check shield cup for proper installation. Do not overtighten. Do not use tools to tighten.
5. Main power line fuse(s) or circuit breaker(s) blown
a. Check main power panel fuse(s). Replace as required.
6. Unit internal fuse blown or loose
a. If blown, double-check input voltage and replace fuse per Section 5.04-C. If fuse blows again, return unit to
an authorized service center.