Tweco 175 SE Arc Master - Manuel (Page 40)

ARC MASTER 175 SE SERVICE
SERVICE 5-4 Manual 0-5054
TIG Welding Problems Continued
!
WARNING
There are extremely dangerous voltages and power levels present inside this product. Do not attempt to repair unless
you are an Accredited Thermal Arc Service Agent and you have had training in power measurements and troubleshooting
techniques. If major complex subassemblies are faulty, then the Welding Power Source must be returned to an Accredited
Thermal Arc Service Agent for repair.
5.04 Power Source Problems
5.05 Key Spare Parts
Description Possible Cause Remedy
12. Arc start is not smooth. A. Tungsten electrode is too large
for the welding cur-rent.
B. The wrong electrode is being
used for the welding job.
C. Gas flow rate is too high.
D. Incorrect shield gas is being
used.
E. Poor work clamp connection to
work piece.
A. Refer to section Tungsten Electrode
Current Ranges for the correct size.
B. Refer to section Tungsten Electrode
Types for the correct electrode type.
C. Select the correct flow rate for the
welding job.
D. Use 100% argon for TIG welding.
E. Improve connection to work piece.
Description Possible Cause Remedy
1. The welding arc cannot be
established.
A. The Primary supply voltage
has not been switched ON.
B. The Welding Power Source
switch is switched OFF.
C. Loose connections internally.
A. Switch ON the Primary supply
voltage.
B. Switch ON the Welding Power
Source.
C. Have an Accredited Thermal
Arc Service Provider repair the
connection.
2. The welding arc cannot be
established when the Over Heat
Indicator is illuminated
The machines duty cycle has been
exceeded
Wait for the Over Heat Indicator to
extinguish before resuming welding
3. Maximum output welding
current cannot be achieved with
nominal Mains supply voltage.
Defective control circuit Have an Accredited Thermal Arc
Service Provider inspect then repair
the welder.
4. Welding current reduces when
welding.
Poor work lead connection to the
work piece.
Ensure that the work lead has a
positive electrical connection to the
work piece.
Part No. Description Part No. Description
W7003003 PCB Front Panel ArcMaster 175 SE W7003018 Inductor 175 SE
W7003007 PCB Control 175 SE W7003020 Output Terminal 175 SE
W7003009 Fan 175 SE W7003022 Panel Front 175 SE
W7003010 Rectifier Input Bridge 175 SE W7003023 Panel Rear 175 SE
W7003011 PCB Power 175 SE W7003024 Panel Cover 175 SE
W7003013 Current Sensor 175 SE W7003025 Panel Base 175 SE
W7003016 Thermistor 175 SE W7003053 ON / OFF Switch