Unit shuts down from overspeed fault unit has 35 hours total run time never ran more than 2 hours 45 minutes rest is excerise time . is this problem with the 15 kw common ?

check your frequency of the ac, if this is high, then adjust the rpms.
If that is fine and it is shutting down, check overspeed adjustment on control board if it has it.

I recently came across a similar situation in a isuzu that took some time to diagnose. What if eventually turned out to be one injector had an intermittent failure and it too out 2 other injectors and the engine shut down. If the vehicle sat for 1/2 hour it restarted and ran again for sometimes days before the fault again appeared. It was tracked down by running the truck on a chassis dyno under load and when the fault appeared each injector was disconnected until the faulty one was revealed. If these symptoms parallel yours I suggest you point the mechanic in that direction .

Replace over speed switch or throttle control.

Leigh,
See my 5/22/12 comments on my "overspeed fault" problem resolution [Generac 43903 standby Generator overspeed indicator on starting] . If it only runs for a few seconds and then quits, you may have a similar condition to the one my unit had. A good technician should be able to diagnose the problem and determine if you have a similar failure to the one I had, or one of the other causes suggested by RSG000.

You have to reset it because it locked out on on under frequency. Just pullout the fuse on the control panel and then reinstall it a couple of seconds later. Now it will reset the fault codes. Hope that helps.

Had a simuliar problem, Bike would have a total shutdown a High Temps/Low Speeds/High RPMs. Everything would reset itself after appox 2 minutes. Everything would shutdown Electric and engine.
2 Harley dealers spent 75 hours diagnosing it, dealer could not reproduce it. Last repair was to replace battery cables. Seems to have fixed it. Have ridden 15oo miles since repair. Problem reacurred once last time I rode. Again complete shutdown bike restored after 2 minutes. Did not happen again the rest of the day over 200 miles

Don't block off any ceiling ducts and see what happens. If you've closed off any forced air ducts, the unit will freeze up, if too many are closed off. Also, if you shut unit off (compressor) give it 5 or 10 minutes before you turn it back on.

Did you remember to set the overspeed shutdown threshold on the control board?

Depending on which type of carburetta this car has, it may be that the rubber diaphram has a tiny pinprick of a hole in it. This will affect the vacumn and the fuel control. An easy way to test this is to allow the car to rest without the engine running for a few minutes, start the engine an increase the power whilst at a standstill and see how long it takes before the engine shuts down, then let it rest again for a few minutes, start the engine and let it run just on tick over, if it carries on running for a much longer period than before then you may have the answer.
Hope this helps Bomber667

bad battery.. RMA that back to where you bought it from. probably wasnt a new battery they sold you. id charge it from completely dead to completely full one more time and if you dont get at least an hour out of the batt then i would return it..