Tweco 75XL Plus PAK Master - Manuel (Page 40)

SERVICE 5-4 Manual 0-2807
5.04 Troubleshooting Guide
A. General
Troubleshooting and repairing this unit is a process which
should be undertaken only by those familiar with high
voltage high power electronic equipment.
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 troubleshoot-
ing techniques.
B. Basic Troubleshooting
This manual covers a basic level of troubleshooting that
requires limited disassembly and measurements. 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 sec-
tion in the order presented.
For major troubleshooting and parts replacement pro-
cedures refer to PAK Master 75XL Plus Automated
Power Supply Service Manual 0-2808.
C. How to use this Guide
The following information is a guide to help the Cus-
tomer/Operator determine the most likely causes for
various symptoms.
This guide is set up in the following manner:
X. Symptom (Bold Type)
Any Special Instructions (Text Type)
1. Cause (Italic Type)
a. Check/Remedy (Text Type)
Locate your symptom, check the causes (easiest listed first)
then remedies. Repair as needed being sure to verify that
unit is fully operational after any repairs.
A. AC Power indicator OFF
1. Switch at customer's main power panel in OFF posi-
tion.
a. Close main power panel switch
2. Input power not properly connected to customer's main
power panel
a. Check that input power is present and unit is
properly connected (refer to Section 3.05, In-
put Power Connections.)
3. Customer's main power line fuse(s) blown
a. Check main power panel fuse(s) and replace
as required.
4. Actual input voltage does not correspond to voltage se-
lection inside unit
a. Check actual line voltage vs. voltage selection
(inside of unit).
5. Unit internal fuse blown or loose
a. If blown, double check input voltage vs. volt-
age selection (inside of unit) and replace fuse
per Section 5.05-B. If fuse blows again, com-
ponents inside the unit may be faulty.
6. Faulty components in unit
a. Return unit to an authorized service center for
repair or have qualified technician repair per
Service Manual.
B. AC Power indicator ON; TEMP indica-
tor ON
1. Airflow obstructed
a. Check for obstructed air flow and correct con-
dition.
2. Fan blocked
a. Check and correct condition
3. Unit is overheated
a. Allow unit to cool down for about 5 minutes.
Make sure the unit has not been operated be-
yond duty cycle limit.
4. Input line voltage is below 75% of rated level
a. Check and connect to proper input power line
5. Faulty components in unit
a. Return for repair or have qualified technician
repair per Service Manual.