Generac Power Systems 17 kW LP manual Test 5 Wire Continuity 12-20 kW, Diagnostic tests, Example

AC generators Part 2

Connect the other meter test lead to Wire 4 (still dis- connected from previous tests). Measure and record static rotor amp draw.

13.Set the AUTO-OFF-MANUAL switch to the MANUAL position. Once the engine starts, repeat Step 12. Measure and record running rotor amp draw with the engine running.

14.Set the AUTO-OFF-MANUAL switch to OFF. Reconnect Wire 4 to the voltage regulator.

RESULTS:

Refer to the chart on this page: “Results - Fixed Excitation Test/Rotor Amp Draw Test”.

Note: A calculated amp draw can be done by taking the battery voltage that is applied divided by the actual resistance reading of the rotor. A resistance reading can be taken by measuring ohms between Wires 4 and 0 at the voltage regulator.

EXAMPLE:

MODEL	5517
WIRE 2 & 6 VOLTAGE	87 VAC
WIRE 11 & 22 VOLTAGE	31 VAC
STATIC ROTOR AMP DRAW	1.0 AMP
RUNNING ROTOR AMP DRAW	1.0 AMP

These results match Column B in the chart. Refer back to Problem 1 Flow Chart and follow Letter B.

Test 5 – Wire Continuity (12-20 kW)

DISCUSSION:

The voltage regulator receives unregulated alternating current from the stator excitation winding, via Wires 2 and 6. It also receives voltage sensing from the sta- tor AC power windings, via Wires 11 and 22. The regulator rectifies the AC from the excitation winding and based on the sensing signals, regulates the DC current flow to the rotor. The rectified and regulated current flow is delivered to the rotor brushes via Wires 4 (positive) and 0 (negative). This test will verify the integrity of Wire 0.

PROCEDURE:

1.Set VOM to its “R x 1” scale.

2.Remove Wire 0 from the voltage regulator, 4th terminal from the top. Also voltage regulator is labeled (-) next to terminal.

3.Connect one test lead to Wire 0, connect the other test lead to a clean frame ground. The meter should read

CONTINUITY.

RESULTS:

If CONTINUITY was not measured, repair or replace the wire as needed.

Section 2.4

Diagnostic tests

H

Below 60 VAC

Below 60 VAC

1.75 - 1.17

1.75 - 1.17

1.59 - 1.07

1.59 - 1.07

1.39 - 0.93

Above 2.5A

G

Above 60 VAC

Above 60 VAC

Zero

Current

Draw

Zero

Current

Draw

INSECTION 2.3 “Problem 1” è

DrawTest (12-20 kW)

F

Below 60 VAC

Below 60 VAC

1.75 - 1.17

1.75 - 1.17

1.59 - 1.07

1.59 - 1.07

1.39 - 0.93

1.75 - 1.17

1.75 - 1.17

1.59 - 1.07

1.59 - 1.07

1.39 - 0.93

E

Below 60 VAC

Below 60 VAC

Above 2.5A

Above 2.5A

Above 2.3A

Above 2.3A

Above 2.0A

Above 2.5A

Above 2.5A

Above 2.5A

Above 2.5A

Above 2.5A

Fixed-Results4TESTExcitation Test/Rotor Amp

MATCH RESULTS WITH LETTER ANDç REFER TO FLOW CHART

BA CD

VAC60AboveVAC60AboveBelow 60 VAC

VAC60BelowVAC60AboveAbove 60 VAC

1.17-1.751.17-1.751.75 - 1.17

1.17-1.751.17-1.751.75 - 1.17

1.07-1.591.07-1.591.59 - 1.07Current

1.07-1.591.07-1.591.59 - 1.07

0.93-1.390.93-1.391.39 - 0.93

1.17-1.751.17-1.751.75 - 1.17

1.17-1.751.17-1.751.75 - 1.17

1.07-1.591.07-1.591.59 - 1.07Current

1.07-1.591.07-1.591.59 - 1.07

0.93-1.390.93-1.391.39 - 0.93

Residualor Volts

Residualor Volts

Zero

Draw

Zero

Draw

Zero

Zero

(Model #)

ALL

ALL

12 kW

14 kW

16 kW

17 kW

20 kW

12 kW

14 kW

16 kW

17 kW

20 kW

Results:

Voltage Results Wire 2 & 6

Voltage Results Wire 11 & 22

Static Rotor Amp Draw

Running Rotor Amp Draw

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