Testing Multifunction AC and DC Circuits

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Technical Support Subject Testing Multifunction AC and DC Circuits Version Document Department Revision Details Revised by Tech Engineering Implemented A EXT-MF-005 Tech Document Release BDJ 26 Oct 2018 DB 26Oct2018 N/A 26Oct2018 Knowledge Base: www.kb.vmacair.com Page 1 of 5 Email: tech@vmacair.com Web: www.vmacair.com Technical Support: 1(888)241-2289 Toll Free:1(800)738-8622 Fax: 1(877)740-3201 SYSTEM OR PARTS AFFECTED • Multifunction Power Systems (MF) with AC-DC Generator INDEX Overview ............................................................................................1 Before you start.................................................................................1 Test Procedures ................................................................................1 If unit fails AC Voltage test...............................................................4 IF UNIT FAILS DC VOLTAGE TEST .................................................5 OVERVIEW When generator output is reported as a problem, refer to the following diagnostic procedures. Before you start When contacting VMAC Technical Support, the following information is required: Customer name Contact information – phone number Contact information – email address System ID number CSR number (if issued) Engine Hours Compressor Hours TEST PROCEDURES The AC Voltage test must be performed before the DC test. Without proper AC output from the generator, there will be no DC output. 240V AC Circuit Testing 1. Start the Raptair MF engine and allow it to warm up for 1 minute. The engine should rev up and then idle down. 2. Turn the Generator on at the control panel. The engine should rev up and stay at high rpm. 3. Using a multimeter set to the AC Volts scale, measure the voltage at the 240V AC receptacles (Figure 1). Record the results in Table 1 below and compare to the specifications. Circuit Specification Measured Voltage X to Y Min. 216 ACV, Max 263 ACV X to Z Min. 216 ACV, Max 263 ACV Y to Z Min. 216 ACV, Max 263 ACV Table 1Technical Support Subject Testing Multifunction AC and DC Circuits Version Document Department Revision Details Revised by Tech Engineering Implemented A EXT-MF-005 Tech Document Release BDJ 26 Oct 2018 DB 26Oct2018 N/A 26Oct2018 Knowledge Base: www.kb.vmacair.com Page 2 of 5 Email: tech@vmacair.com Web: www.vmacair.com Technical Support: 1(888)241-2289 Toll Free:1(800)738-8622 Fax: 1(877)740-3201 Figure 1 120V AC Circuit Testing 4. Ensure machine is running, main breaker is in ON position and neither of the 20A pop breakers is tripped. 5. Locate the two 120V receptacles, above the 240V outlets and LED Voltage display (Figure 2).Use a multimeter set to its AC voltage setting to measure between the small slot and large slot in each of the 4 120V AC outlets. Record the results in Table 2 below and compare to the specifications. Circuit Specification Large slot – Small slot Left Outlet, Left side Min. 110V, Max. 130V Left Outlet, Right side Min. 110V, Max. 130V Right Outlet, Left side Min. 110V, Max. 130V Right Outlet, Right side Min. 110V, Max. 130V Table 2 6. Press the “test” button on the GFCI and it should trip. Press reset button to re-enable receptacle. GFCI’s will not reset if the generator is not making voltage The generator’s LED Voltage display (Figure 2) has 5 LEDs. The bottom LED indicates “210V”, however it simply indicates that the generator is producing somewhere between 0V and 210V. If only the lowest LED is lit, the generator is likely not in fact producing 210V but something much lower. If output from the 240ACV outlets was good but 0V is measured in any of the 120ACV circuits above, check to see if the GCFI has tripped. If the GCFI is tripped, try to reset it. If the GCFI will not reset, replace the outlet.Technical Support Subject Testing Multifunction AC and DC Circuits Version Document Department Revision Details Revised by Tech Engineering Implemented A EXT-MF-005 Tech Document Release BDJ 26 Oct 2018 DB 26Oct2018 N/A 26Oct2018 Knowledge Base: www.kb.vmacair.com Page 3 of 5 Email: tech@vmacair.com Web: www.vmacair.com Technical Support: 1(888)241-2289 Toll Free:1(800)738-8622 Fax: 1(877)740-3201 Figure 2 Testing DC Circuits 7. Select the DC voltage setting on the multimeter. Measure the open circuit voltage between the positive and negative Weld DC terminals in each of the weld settings-12V/24V/36V/48V. Record the measurements in Table 3 and compare with the specifications. Weld Setting Specification Measured Voltage 12V 13-17 Volts DC 24V 26-30 Volts DC 36V 39-48 Volts DC 48V 52-62 Volts DC Table 3 240V 1PH Outlet 240V 3PH Outlet 120V Receptacles LED Voltage Display Weld Positive DC terminal, Dinse 50 20 Amp Circuit Breaker. Push reset 20 Amp Circuit Breaker. Push reset Weld Negative DC terminal, Dinse 50 30 Amp Circuit BreakerTechnical Support Subject Testing Multifunction AC and DC Circuits Version Document Department Revision Details Revised by Tech Engineering Implemented A EXT-MF-005 Tech Document Release BDJ 26 Oct 2018 DB 26Oct2018 N/A 26Oct2018 Knowledge Base: www.kb.vmacair.com Page 4 of 5 Email: tech@vmacair.com Web: www.vmacair.com Technical Support: 1(888)241-2289 Toll Free:1(800)738-8622 Fax: 1(877)740-3201 8. If the values recorded in Table 3 are all correct but the unit will not weld or charge properly, generator replacement is required due to faulty non-serviceable internal generator components. • If the AC voltage test results do not meet specification, then go to Step 9. • If the DC voltage test results do not meet specification, replacement of the generator PC board is required. Contact VMAC Technical Support for information on the A500199 PC Board installation. It is possible for a faulty PC board to damage the welder control box. It is not possible to test the welder control box without first ensuring a good PC board is in place. When the generator repair is complete go to step 17. IF UNIT FAILS AC VOLTAGE TEST 9. Turn MF off and disconnect the battery. 10. With the generator cover off, identify the bridge rectifier (Figure 3). Figure 3 11. Note the wire positions on the bridge rectifier for reassembly and disconnect them from the bridge rectifier. 12. Set the multimeter to “diode check” with the leads connected for voltage measurement. Use Figure 4 as a guide for pin location. 13. Connect the ground lead of the multimeter to pin 5 and the positive lead to the pins below. Resulting voltage should be: a. Probe pin 1: 0.4-0.5V b. Probe pin 2: 0.4-0.5V c. Probe pin 3: 0.4-0.5V If any pin produces a short or open circuit, the bridge rectifier is failed. Bridge RectifierTechnical Support Subject Testing Multifunction AC and DC Circuits Version Document Department Revision Details Revised by Tech Engineering Implemented A EXT-MF-005 Tech Document Release BDJ 26 Oct 2018 DB 26Oct2018 N/A 26Oct2018 Knowledge Base: www.kb.vmacair.com Page 5 of 5 Email: tech@vmacair.com Web: www.vmacair.com Technical Support: 1(888)241-2289 Toll Free:1(800)738-8622 Fax: 1(877)740-3201 14. Connect the positive lead of multimeter to pin 4 and the negative lead to the pins below. Resulting voltage should be: a. Probe pin 1: 0.4-0.5V b. Probe pin 2: 0.4-0.5V c. Probe pin 3: 0.4-0.5V If any pin produces a short or open circuit the bridge rectifier is failed Figure 4 15. If the bridge rectifier has failed, replace the bridge rectifier, reassemble the generator, and re-test. 16. If the bridge rectifier passes the test, generator replacement is required due to faulty non-serviceable internal generator components. IF UNIT FAILS DC VOLTAGE TEST 17. When the generator repair is complete, if the DC test results still do not meet specifications as shown in step 8, turn the generator off. 18. Replace the welder control box unit. 19. Start the MF engine and allow it to warm up for 1 minute. 20. Turn the generator on and verify that output values are now correct. If you have any questions, please call VMAC Tech Support 1-888-241-2289