Generac Power Systems IM Series - Manual (Page 12)

Test Between Isolated Windings:- To test between iso­
lated Stator windings, proceed as follows:
1. Connect RED lead of Hi-Pot tester to terminal end of
Wire 11, BLACK test lead to Wire 2 terminal end.
2. Turn tester switch ON and check that Pilot Light is ON.
3. Set Voltage Selector Switch to 1500 voits- APPLY
VOLTAGE FOR ONE SECOND ONLY. Observe tester
Breakdown lamp. Turn tester switch OFF and reset Vol­
tage Selector Switch to 500 volts.
Test Between Parallel Windings:- Test between paral­
lel Stator windings as follows:
1. Set tester Voltage Selector Switch to 500 volts.
2. Connect tester RED test lead to Wire #11, BLACK test
lead to Wire 33.
3. Turn tester switch ON and check that Pilot Light is ON.
4. Apply voltage for one second while observing the
Breakdown lamp. Then, turn tester switch OFF.
RESULTS: If tester Breakdown lamp comes ON
during any one second test, clean and dry the stator.
Then, repeat the breakdown test. If Breakdown lamp
Illuminates after drying, replace the Stator Assemb­
ly-
Testing Rotor Insulation for Breakdown
D
Remove generator cover to gain access to the Rotor
slip rings and brushes. ,
E
Remove all wires that connect to the Brushes. Then,
test Rotor insulation as follows:
1. Connect tester RED test lead to the positive {+) Rotor
slip ring (nearest the Rotor bearing).
2. Connect BLACK test lead to a clean frame ground.
3. Turn tester switch OFF.
4. Plug tester into a 120 volts wall socket.
5. Set Voltage Selector Switch on tester to 500 volts.
6. Turn tester switch ON and check that Pilot Light is ON.
7. Set Voltage Selector Switch to 1250 volts and observe
the tester breakdown lamp. Then, turn tester switch OFF.
RESULTS:- If tester breakdown lamp lllumlates
during the 1 second test, drying of the generator may
be necessary. After drying, repeat the Hl-Pot test. If
Rotor windings fall the second test (after drying),
replace the Rotor assembly.
Cleaning the Generator
Removed caked on or greasy dirt with a soft brush or a
clean, damp doth. A vacuum system may be used to pick
up loosened dirt. Loose dust and dirt may also be
removed using low pressure, dried air (25 psi maximum).
CAUTION!: Do NOT use a forceful spray of water to
clean generator. Some of the water will be retained
on generator windings and will cause serious
problems.______________________________________
Drying the Generator
1. Open the main drcuit breaker or main line switch. NO
ELECTRICAL LOADS MUST BE CONNECTED TO
GENERATOR WHILE DRYING.
2. Remove the generator cover (see illustration "B" on
previous page).
3. Disconnect Wire #4 from the Electronic Voltage
Regulator.
4. Provide an external source to blow warm, dry air
through the generator. Do NOT exceed 185' F. (85* C.).
5. Start the engine, let it run for 2 to 3 hours.
6. Stop the engine and retest Stator and Rotor windings.
10