Maintenance And Lubrication; Ground Test Procedure - Lincoln Electric SHIELD-ARC 400AS-50 Operating Manual

FOR ENGINE
powered equipment
For instructions on lubrication and maintenance of the
engine, refer to the engine instruction manual.
Cylinder head nuts must be pulled down after 25 hours
operation and no later - see Engine Manual.
All internal and external connections should also be checked
to make certain they are tight.
Running In
It is not necessary to gradually run in a new or factory rebuilt
engine and any prolonged light load running during the early life
of the engine can prove harmful to the bedding in of piston rings
and liners.
SEE "IMPORTANT NOTE ABOUT "RUNNING IN" YOUR
DIESEL ENGINE" ON PAGE 4.
WELDER
General
It is good practice to blow out the welder with compressed air and
check all internal and external connections for tightness every 2-
3 months. This welder is equipped with a double-seal ball bearing
having sufficient grease to last the life of the bearing.
WARNING
This procedure is only suitable for applications using DC
mega testers up to 500V.
Note: This procedure is for 'machines as built' many modifications
could have taken place over the life of a particular machine, so
details of this procedure may need to be 'adjusted' to suit these
modifications.
For prompt service contact your local authorised Lincoln field
service shop.
The insulation resistance values listed below are from Australian
Standard AS1966.2.
1. Ensure engine is stopped.
2 Remove welding leads and disconnect any auxiliary
equipment cables.
3. Disconnect the leads from the battery charge alternator
(mounted on the engine).
4. Disconnect the negative and positive battery leads.
5. Jumper together the positive, negative and both AC
terminals of the two bridge rectifiers (one mounted on the
rear of the control panel and the other is on the brush
holder bracket).
6. Place the key switch in the 'RUN' position and the aux
switch to the 'ON' position.
7. Remove the thermostart lead from terminal No 5 on the key
switch.
8. Remove the earth leads from:
The bridge rectifier (mounted on the brush holder
bracket).
IF ANY PROBLEMS ARE ENCOUNTERED REFER TO YOUR NEAREST AUTHORISED LINCOLN FIELD SERVICE SHOP
IMA 554C

MAINTENANCE AND LUBRICATION

GROUND TEST PROCEDURE

Shield-Arc 400AS-50
Communicator and Brushes
The commutator and brushes are inspected by opening the doors
and removing generator covers.
The brushes on the generator and alternator are properly
adjusted before the machine leaves the factory. No particular
attention is required to keep the brushes in good condition,
however as the brushes wear out they must be replaced with new
ones. One complete set of brushes should always be kept on
hand.
Before fitting replacement brushes, twist the brush pig tail at its
entrance to the brush until the strands are tightly packed and no
part of the pig tail protrudes beyond the brush surface in the pig
tail slot. When the brush is placed in the holder, clear the pig tail
from the side of the holder to allow free radial movement of the
brush.
New brushes must be bedded in before they can be used on the
machine. This is accomplished by placing the new brush in
position in the holder with a piece of medium sandpaper (never
use emery cloth) placed under the brush. A second person
should hold the brush in its normal position by a slight pressure
of the fingers. The sandpaper then should be drawn in the
direction of generator rotation under the brush with the back of
the sandpaper held closely in contact with the commutator or slip
ring. This will wear the end of the brush down to the proper curve.
When the end of the brush has the proper curve, the operation is
complete. Care should be taken to blow all carbon dust away from
the commutator or slip rings.
The commutator and slip rings require very little attention. They
should be cleaned from time to time with a clean rag or, while
running, with a piece of fine sandpaper. Never use emery cloth or
paper or organic solvents for this purpose.
The water temperature gauge and sender.
The voltmeter.
The stop solenoid (mounted in the engine fuel injector
pump)
The hour meter and engine watcher warning light (if
fitted).
9. Auxiliary Circuit Test: Connect one lead of the mega tester
to the frame of the machine and the other lead to the
'active' terminal of one of the 240V aux. outlets. Apply the
test. (Minimum resistance 1MΩ)
10. Welding Circuit Test: Connect one lead of the mega tester
to the frame of the machine and the other lead to the
positive output stud. Apply the test. (Minimum resistance
1MΩ)
11. Field Circuit Test: Connect one lead of the mega tester to
the frame of the machine and the other lead to the positive
output stud. Apply the test. (Minimum resistance 1MΩ)
12. Aux. to Weld Circuit Test: Connect one lead of the mega
tester to the 'active' terminal of one of the 240V aux. outlets
and the other to the positive output stud. Apply the test.
(Minimum resistance 10MΩ)
13. Aux. to Field Circuit Test: Connect one lead of the mega
tester to the 'active' terminal of one of the 240V aux. outlets
and the other to one of the slip ring brush pig tails. Apply
the test. (Minimum resistance 1MΩ)
14. Weld to Field Circuit Test: Connect one lead of the mega
tester to the positive output stud and the other lead to one
of the slip ring pig tails. Apply the test. (Minimum resistance
1MΩ)
15. Remove all jumper
disconnected during this procedure.
leads. Reconnect all leads
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