ESAB ESP-150 Manuel D'instruction page 247

SECTION 5
Be sure that all primary power to
the machine has been externally
disconnected. Open wall discon-
nect switch or circuit breaker be-
fore attempting inspection or work
inside of the power supply.
Voltages in plasma cutting equip-
ment are high enough to cause
serious injury or possibly death. Be
particularly careful around equip-
ment when the covers are re-
moved.
Be sure that all primary power to the
machine has been externally dis-
connected. Open wall disconnect
switch or circuit breaker before at-
tempting inspection or work inside
of the power supply.
MAINTENANCE
If this equipment does not operate properly, stop work immediately and investi-
gate the cause of the malfunction. Maintenance work must be performed by an
experienced person, and electrical work by a trained electrician. Do not permit
untrained persons to inspect, clean, or repair this equipment. Use only recom-
mended replacement parts.
A. INSPECTION AND CLEANING
Frequent inspection and cleaning of the ESP-150 cutting machine is recommended.
Some suggestions for inspecting and cleaning are as follows:
1. Check work cable to work piece connection.
2. Check safety earth ground at workpiece and at power source chassis.
3. Check heat shield on torch. It should be replaced if damaged.
4. Check the torch electrode and cutting tip for wear on a daily basis. Remove
spatter, replace if necessary.
5. Make sure cable and hoses are not damaged or kinked.
6. Make sure all plugs, fittings, and ground connection are tight.
CAUTION: Water occasionally accumulates in compressed air lines. Be sure
to direct the first blast of air away from the equipment to avoid damage.
7. With all input power disconnected, and wearing proper eye and face protec-
tion, blow out the inside of the cutting power supply using low- pressure dry
compressed air.
8. Occasionally bleed water from the filter beneath the air regulators.
B. FLOW TESTING
Improper flows can cause short life on the consumables, poor starting, bad cuts,
or overheated torches. The flows given below are "cold" flow (no arc). To avoid
fatal shock, follow the steps below to assure safe flow measurement.
1. Shut off input power at the main disconnect switch.
2. Lift the top lid of the ESP-150 and unplug the torch switch cord.
3. Close the lid.
4. Turn on the power at the main disconnect switch.
5. Place gas mode selector switch (OSS) in START/SHIELD position.
6. Place power ON-OFF switch (ROS) to ON.
7. Check flow measurements with P/N 19765 flow measuring kit.
8. Place mode selector switch (OSS) in CUT position and check CUT flow with
P/N 19765 flow measuring kit.
9. Place ROS switch to OFF.
10. Turn off power at main disconnect switch.
11. Reconnect torch switch plug inside console.
PT-26 Plasma Gas Flow (No Arc):
Nitrogen or Air @ 60 psig: 110 cfh; H-35 @ 90 psig: 130 cfh
PT-26 Start Gas Flow:
Nitrogen or Air @ 40 psig: 75 cfh
PT-26 Shield Gas Flow:
Air or Nitrogen @ 85 psig: 200 cfh minimum.
C. SPARK GAP ADJUSTMENT
The spark gap, which is part of the high frequency generator, is factory set at
0.025-in. (+/- 0.002). After extended operation or if erratic operation is noted, it
may be necessary to readjust or replace the electrodes (634098). Use a feeler
gauge when readjusting the gap. (See form 11-831, "Recommended Installation
and Test Procedures for High-Frequency Stabilized Arc Welding Machines", packed
with the unit.) Cleaning or dressing of the spark gap electrodes is not recom-
mended. When replacement is necessary, both electrodes should be replaced.
241
MAINTENANCE