Section 6
DIAGNOSTIC TESTS
Introduction
The “Diagnostic Tests” in this chapter may be per- formed in conjunction with the “Flow Charts” of Section 5. Test numbers in this chapter correspond to the numbered tests in the “Flow Charts”.
Tests 1 through 19 are procedures Involving problems with the generator's AC output voltage and frequency (Problems 1 through 5 in the “Flow Charts”).
Tests 19 through 54 are procedures involving prob- lems with engine operation (Problems 6 through 14 in the “Troubleshooting Flow Charts”).
It may be helpful to read Section 2, “Measuring Electricity”.
NOTE: Test procedures in this Manual are not nec- essarily the only acceptable methods for diagnos- ing the condition of components and circuits. All possible methods that might be used for system diagnosis have not been evaluated. If any diag- nostic method is used other than the method pre- sented in this Manual, the technician must ensure that neither his personal safety nor the product's safety will be endangered by the procedure or method that has been selected.
Test 1 - Check No-Load Voltage and
Frequency
PROCEDURE:
1.Disconnect or turn OFF all electrical loads connected to the generator.
2.Set a volt meter to measure AC voltage.
3.Reset all circuit breakers to the on position.
4.Turn the Idle Control switch to OFF.
5.Start the engine and let it stabilize and warm up.
50A240
Figure 6-1. – VOM Test Leads Connected to 50A
Outlet
*NOTE: If the generator is not producing AC Power, loss of governor control may occur caus- ing an overspeed or extremely high RPM condi- tion. If this condition occurs manually control throttle (60Hz /3600 RPM) to perform test.
6.Place the meter test leads into the 50A outlet. See Figure
7.Read the AC voltage.
8.Connect a AC frequency meter as described in Step 6.
9.Read the AC frequency.
RESULTS:
For units rated 60 Hertz, no load voltage and frequen- cy should be approximately
TEST 2 - CHECK MAIN CIRCUIT BREAKER
PROCEDURE:
The generator has seven circuit breakers located on the control panel. If outlets are not receiving power, make sure the breakers are set to ON or “Closed”.
If a breaker is suspected to have failed, it can be tested as follows (see Figure
1.Set a Volt meter to measure resistance.
2.With the generator shut down, disconnect all wires from the suspected circuit breaker terminals to prevent interaction.
3.With the generator shut down, connect one meter test lead to a one terminal of the breaker and the other meter test lead to the other terminal. See Figure
4.Set the breaker to its ON or “Closed” position. The meter should read CONTINUITY.
5.Set the breaker to its OFF or “Open” position and the meter should indicate INFINITY.
RESULTS:
1.If the circuit breaker tests good, refer back to the flow chart.
2.If the breaker tests bad, it should be replaced.
A B
00.00
ON | 50A |
| |
OFF | C.B. |
A B
Figure 6-7. – 50 Amp Breaker Test Points
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