Tweco PAK 44G - Manual (Page 31)

Manual 0-2686 25 CUSTOMER/OPERATOR SERVICE
b. High coolant conductivity
5.04 Troubleshooting Guide
A. Basic Troubleshooting
This Sub-Section covers basic troubleshooting that re-
quires no disassembly or electronic measurements. It is
helpful for solving many of the common problems that
can arise with this system. Since the malfunction may be
due to a faulty connection rather than a faulty compo-
nent, be sure to check all connections to a component that
appears to be malfunctioning.
NOTE
For more advanced troubleshooting and service
instructions refer to the Service Manual 0-2687.
The troubleshooting is arranged in the normal operating
sequence of the unit for easy reference. Each problem
has listed next to it the possible causes and the remedy.
NOTE
The diagram in Appendix IV shows the timing se-
quence of the Pak unit as a gouge is made with one
interruption as the torch passes over a hole in the
workpiece.
B. 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:
Major Problem Area based on normal
operation
Any special instruction, setup and normal function
X. Symptom (Bold Type)
Any Other 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
the unit is fully operational after any repairs.
WARNING
Voltages in Plasma Gouging equipment are high
enough to cause serious injury. Use particular care
around equipment when covers are not in place.
Main Power Problems
1. Close the external input power switch to supply AC
voltage to the Power Supply.
• Red AC POWER indicator comes ON
2. Place the Power Supply ON/OFF power switch to ON
• Amber READY indicator comes ON
• Gases flow for 2 seconds.
If this does not happen, check as follows:
A. No AC POWER indicator
1. Blown fuse or open circuit breaker at primary
a. Replace fuse or reset breaker
B. No READY indicator
1. Front Panel ON/OFF (SWl) is turned OFF
a. Place switch to ON position
2. Leads Door Interlock Switch (SW3) not actuated
a. Check switch and actuator tab for alignment
3. Blow Fuse 3FU
a. Check fuse
4. Coolant Pressure Interlock PSl open; pressure below 40
psi (2.8 kg/cm2)
a. Check coolant level
b. Clean pump filter screen
5. Pressure Switch (PSl) not satisfied
a. Adjust input pressure (120 psi)
6. Transformer overheated
a. Allow unit to cool down
C. Fan/Pump will not start
1. Blown Motor Circuit Fuse 4FU, 5FU & 6FU
a. Replace Fuses
2. Rotation Switch SW6 OFF (See NOTE)
a. Switch to proper position
NOTE
Fan Rotation Switch was removed from units
manufactured after 1996.
3. Broken or Loose Fan Belt
a. Replace or tighten