Generac — Test Rotor Insulation
Testing & diagnosis
From a Generac service manual covering: 9202-1, 9203-1, 9204-1, 9205-1, 9206-1, 9207-1, 9290-2, 9509-2, 9592, 9593-0, 9593-1, 9593-2…. Check it applies to your exact model before use.
Applies to: Generac 9592
Before you start
- Do not exceed 1000 volts and do not apply voltage longer than 1 second.
Procedure
- Disconnect wires from the rotor brushes or remove the brush holders with brushes.
- Connect the positive test lead to the positive slip ring (nearest the rotor bearing).
- Connect the negative test lead to a clean frame ground such as the rotor shaft.
- Apply 1000 volts; do not apply voltage longer than one second.
- If breakdown indicated, clean and dry the rotor then repeat; replace rotor if it fails the second test.
Tools required
- megohmmeter Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Rotor test voltage 1000 volts
- Rotor minimum insulation resistance 1.5 megohms
Full service-parts list: Generac 9592 →
Source: Generac service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.