Current Sense Board Test Procedure - Lincoln Electric SAE-300 HE Service Manual

LINCOLN ELECTRIC

CURRENT SENSE BOARD TEST PROCEDURE

Service and repair should be performed by only Lincoln Electric factory trained personnel. Unauthorized
repairs performed on this equipment may result in danger to the technician or machine operator and will
invalidate your factory warranty. For your safety and to avoid electrical shock, please observe all safety
notes and precautions detailed throughout this manual. If for any reason you do not understand the test
procedures or are unable to perform the test/repairs safely, contact the Lincoln Electric Service Department
for electrical troubleshooting assistance before you proceed. Call 1-888-935-3877.
TEST DESCRIPTION
This test will determine if the Current Sense Board is functioning properly.
MATERIALS NEEDED
Volt/Ohmmeter
Wiring Diagram
TEST PROCEDURE
1. Turn off the engine on the SAE-300 HE machine.
2. Open the side covers and secure them with the hooks provided.
3. Locate the current sense board on the left rear side of the front panel. See Figure F.20. See Wiring
Diagram.
4. Place the 'Run/Stop' switch into the 'Run' position. See Wiring Diagram.
5. Using a volt/ohmmeter, measure the voltage from current sensor board plug pin 1 to pin 2. Normal
reading is 12 VDC. See Figure F.21. See Wiring Diagram.
6. Start the engine on the SAE-300 HE machine.
7. Using a volt/ohmmeter, measure the voltage from current sensor board plug pin 4 to pin 2. Normal
reading is 12 VDC with the machine at low idle and less than 1 VDC with the machine at high idle
(under load). See Figure F.21. See Wiring Diagram.
8. With the machine running and in low idle, apply a load to the 120 VAC receptacle. The machine
should go into high idle automatically.
9. Turn off the engine on the SAE-300 HE machine.
10. If any of the tests fail, the current sense board may be faulty.
11. If faulty, perform the Current Sense Board Removal And Replacement Procedure.
12. When testing is complete, close the side covers.
SAE-300® HE Service Manual
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