Lincoln Electric POWER-ARC 4000 SVM103-A Service Manual page 52

F-11
FIGURE F.1 - LOCATION OF LEAD 200A FOR ROTOR VOLTAGE TEST
CONNECTION
TEST PROCEDURE
1. With the 5/16" nut driver, remove the 4
sheet metal screws that hold the top cover
to the control box. Remove the top cover.
2. Start the machine and run it at high idle.
Set the output control (rheostat) at the
MAXIMUM or GENERATOR setting.
3. Set the volt/ohmmeter at the DC position.
4. Place the positive probe on lead 200A
(Blue and Brown wires joined together)
where it connects at the back of the rheo-
stat. See Figure F.1 for location. Place
the negative probe on the machine ground
stud or any other good, unpainted ground.
POWER-ARC 4000
TROUBLESHOOTING & REPAIR
ROTOR VOLTAGE TEST (continued)
LEAD 200A
GROUND STUD
OUTPUT PANEL
5. Check the voltage reading on the
volt/ohmmeter. It should read 45 - 48
VDC.
6. If the voltage is low or not present, the
generator field circuit is not functioning
correctly. Proceed with the Rotor
Resistance Test. C1, R1, or D1 may also
be faulty.
7. If rotor voltage is correct, the generator
field is okay. Replace the top cover on the
control box. Tighten the 4 sheet metal
screws with the 5/16" nut driver.