Lincoln Electric COMMANDER 400 SVM133-B Service Manual page 122

F-68
CONTROL BOARD POWER SUPPLY TEST (continued)
TEST PROCEDURE
NOTE 1: In this test procedure, the positive output
stud is used for common.
NOTE 2: This test procedure does not test the engine
control power supply portion of the control
board.
1. Using the 5/16" nut driver, open the control panel
and tilt out. Remove the control board cover.
2. Using the control PC board layout, locate capaci-
tor C112 (Figure F.31) and scrape the environmen-
tal coating off the negative lead.
machine.
WARNING
There are high voltages present inside
the control box while the machine is
running. THE VOLTAGES ARE HIGH
ENOUGH TO KILL. Use extreme cau-
tion to avoid the backside of the recep-
tacles, breakers, and terminal strip while checking
voltages inside the control box.
Measurement Point
J5 pin 2 to common
J4 pin 6 to common
J5 pin 7 to common
C112 neg. lead to common
J8 pin 2 to J8 pin 3
J20 pin 3 to J20 pin 4
C112
J2
J6 J5
TROUBLESHOOTING AND REPAIR
Start the
Table F.2
Voltage
15 VDC +/- 5%
10 VDC +/- 5%
5 VDC +/- 5%
-10 VDC +/- 5%
24 VDC +/- 5%
15 VDC +/- 5%
Figure F.31 Control Board Plugs C112 & J2
J20
J1
J8 J7
J4
COMMANDER 400
3. Refer to the Stator Voltage Test, step 10, to test
the E1-E2 stator winding that powers the control
PC board. If the voltage is correct, proceed to
step 4. If the voltage is incorrect, shut down the
machine, unplug J2, restart the machine, and
check the voltage again at J2 pins 1 to 4. If the
voltage is still incorrect, abort the "Control Board
Power Supply Test" and proceed to the "Stator
Resistance Test".
4. With the machine running, measure the voltages at
the control board per the following table.
5. If any of the voltage checks in the Table F.2 below
are incorrect, replace the control board.
6. If the test is complete, replace the control board
cover and close the control panel.
Description
+15V supply for display
+10V supply for weld control & exciter module
+5V supply for microprocessor
-10V supply for weld control
+24V supply for 2-4 circuit
+15V supply for CV SCR gate drive circuit
C112
Pin #1
Pin #3
J22
F-68
Pin #2
Pin #4
Plug J2