High generator voltage

[danjames]

Generator voltage measured at outlets inside bus is 155V without load. I would expect it to be higher than 120V unloaded, but this seems higher than it should be. Does anyone have some suggested troubleshooting steps? I would add some loads to see if it drops, but I don't want to chance damaging components with the high voltage. I appreciate any advice that can be provided. Thanks.

Yanmar Model 4TN82E-UK 12.5KW

[Dave Stokes]

following since I just discovered a similar problem on leg two with my Powertech 15k

[SNOWBIRD]

Voltage is a function of RPMs. Does the genset sound like it is running faster than normal?

Do not run loads at that high voltage.

[konehd]

RPM sets the frequency, voltage is set by the excitation from the voltage regulator...

Dave, if you have high voltage on one leg, whats the other?



/Joe

[Bill Pape]

turn off the power to the bird , 155 is not good it will fry appliances, charger etc. measure both legs at the generator circuit breakers.

[danjames]

Raining tonight so I am not going out to troubleshoot. Reviewing generator wiring diagram, it appears problem is most likely in the end bracket area, specifically the automatic voltage regulator. Will check it out this weekend and update this post.

[danjames]

The generator model is Kohler 12.5CCO67.

[sfedeli]

Prior to replacing the regulator, you should check readings across the slip-rings, stator, rotor and individual brushes. The new voltage regulators are not cheap and not very durable. Your Kohler manual has a good flow-chart/troubleshooting guide on pages 7 & 8 for the regulator.

[Rick Davis]

If you find you need to start throwing $$ at replacing parts, you might start saving your pocket change to save up the $1,200 to $3,000 it will take to change the Kohler out to a new brushless solid state head, especially if you plan to keep your Bird.

[danjames]

Sfedeli,

I have the operation and installation manual but the pages you reference do not have a troubleshooting flowchart or guide. There is a troubleshooting guide in the back of the manual but it is very generic and speaks nothing of the voltage regulator. Would you mind sending me snapshots or PDFs of the pages you have? I would be much obliged. If those documents are already on WOG, please direct me to them. Thanks.