Kohler — Underfrequency Adjustment (Over/Underfrequency Relay, Decision-Maker 3+)

Adjustments

From a Kohler service manual covering: 125REOZJG, 150 REOZJ4, 150REZG, 175REOZT4, 2000REOZM, 2000REOZMD, 2250REOZDD, 275REOZJD, 275REOZJE, 400REZX, 400RZX, 48REOZK4…. Check it applies to your exact model before use.

Applies to: Kohler 125REOZJG, Kohler 150 REOZJ4, Kohler 150REZG, Kohler 175REOZT4, Kohler 2000REOZM, Kohler 2000REOZMD, Kohler 2250REOZDD, Kohler 275REOZJD, Kohler 275REOZJE, Kohler 400REZX, Kohler 400RZX, Kohler 48REOZK4

Procedure

1. Turn underfrequency adjustment potentiometer fully clockwise (CW).
2. Place master switch in RUN to start the generator set.
3. Adjust governor per engine operation manual, engine service manual, or governor section of this manual.
4. Slowly turn underfrequency potentiometer counterclockwise (CCW) until LED starts flashing; after about 10 seconds the set shuts down on auxiliary fault.
5. Place master switch to OFF/RESET to reset the controller.
6. Place master switch to RUN to start the generator set.
7. Readjust the governor to the desired frequency as required.
8. Place master switch to OFF/RESET to stop the generator set.

Full service-parts list: Kohler 125REOZJG →, Kohler 150 REOZJ4 →, Kohler 175REOZT4 →, Kohler 2000REOZM →, Kohler 2000REOZMD →, Kohler 2250REOZDD →, Kohler 275REOZJD →, Kohler 275REOZJE →, Kohler 48REOZK4 →

Source: Kohler 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.

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