Generac RN100 — Utility Voltage Checks
Testing & diagnosis · power monitor relay
For the Generac RN100, from the Generac service manual.
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Before you start
- Contact with live terminals causes fatal shock
Procedure
- Turn ON UTILITY power supply
- Check voltage across N1-N2, N2-N3, N1-N3
- Check voltage across N1-NEUTRAL, N2-NEUTRAL, N3-NEUTRAL
- Locate 3-phase power monitor relay
- Verify LED green and ON
- If LED not ON rotate potentiometer counter-clockwise
- When voltage correct turn OFF UTILITY supply
Tools required
- AC voltmeter Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- 208V system: LED green ON
- 480V system: LED NORM indicator ON
- Factory dropout: 80% nominal (208V=166V, 480V=384V)
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.