Tweco 3000 Merlin - Manual (Page 49)

Manual 0-2532 5-5 SERVICE
3. Faulty power supply
a. Isolate and replace component(s) per Service
Manual.
M. Weak or sputtering pilot; HF stays on during
pilot
1. Plasma gas pressure too high
a. Adjust pressure
2. Low OCV (normal 290-350 VDC) caused by im-
proper connection of voltage selection bus bars
a. Check input voltage connections
3. Faulty power supply
a Isolate and replace component(s) per Service
Manual.
N. No pilot; PILOT indicator ON; Strong spark
visible at spark gap points in Arc Starter Box
1. Faulty torch parts
a. Repair per Torch Manual
2. Faulty power supply
a. Isolate and replace component(s) per Service
Manual.
O. Pilot arc ON; No main arc transfer (torch
brought within range of work)
1. Work cable not connected
a. Connect work cable securely
2. Faulty power supply
a. Isolate and replace component(s) per Service
Manual.
5.05 Basic Parts Replacement
NOTE
For more detailed Parts Replacement Proce-
dures and Replacement Parts refer to Power
Supply Service Manual 0-2533
The parts replacement procedures described in this
manual are for basic replacement of parts that requires
limited disassembly of the Power Supply.
WARNING
Disconnect primary power from the source
before disassembling the power supply.
A. Side Panel Removal
The replacement of the fuse and filter assemblies can
be made through the left and right sides of the Power
Supply. Remove the Right and Left Side Panels as fol-
lows:
1. Locate the removable Left and Right Side Panel
of the Supply as viewed from the front of the unit.
Left Side Panel
Screws
(10 Places)
A-00954
Figure 5-3 Side Panel Screw Removal
2. Remove the ten screws that secure each side
panel to the Power Supply.