cirruspilot

Model 0076453 SN 4361184.  15 KW Propane.  Starts great upon manual utility loss but no output.
Ran unit in manual with utility on and no output.  Pulled genset top plate and no voltage at breaker input.  The two fuses in the top genset panel are OK.  I appreciate possible solutions.
Thanks, Don

Quote
78buckshot
I looked up the serial number, from what I can see you have a controller with LED's that signal a fault. That unit will continue to run even though it is not producing voltage. The first thing I suggest is check for continuity through the DPE breaker. You'll find the breaker near the circuit board mounted to the steel control panel. Sometimes the circuit breaker falls apart due to age and heat, it's an automatic reset breaker, one wire in and one wire out, black plastic about 2.5 in. long, 1/2 wide. If that checks out ok and is in the closed position then we'll move on to the next test.
Quote
cirruspilot
Unfortunately the breaker is not open.
Regards, Don
Quote
78buckshot
So you found the DPE breaker and disconnected the wires from it to test? Now lets check rotor/ brush/slip-ring resistance. On the bulkhead between the engine and control/battery compartment you will see two sets of connectors. I can't remember which one has the wires we need but you will be looking for the connector with wires coming from the bottom of the alternator can. In that harness will be two small wires marked #4 and #0, unplug the connector from the bulkhead so you can measure resistance on the harness side. DON'T probe the sockets, use paperclips to backprobe the connector and read resistance between #4 and #0, rotate the engine and read again, we want to see less than 25 ohms through that series of components.
Quote
cirruspilot
42 ohms and after rotation 29 ohms
Don
Quote
78buckshot
Try a few more readings with rotation between each, if we see higher resistance in some spots then it's time to tear it down for slip-ring cleaning.
Quote
cirruspilot
I’ll do that tomorrow.   This generator has less than 5 hours on it.  I guess that could be bad or good.  It is stored inside and wheeled out during hurricane season.
 Thanks 
Quote
78buckshot
ok
Quote
cirruspilot
Resistance readings after many quick (cranks).63, 32, 28, 28, 25, 25, 29, 40, 27.
if the conclusion is slip-ring cleaning, how big a job do you estimate and is there any chance I could perform it?
 Thanks, Don
Quote
cirruspilot

I was wondering......the ATS is not switching when main breakers are pulled.  It seems that the ATS would trip regardless??  

Also if I wanted to run the generator without any ATS, should a normal Generac put out voltage or could the control wires prevent output?
 Thanks, Don

Quote
78buckshot
The erratic readings are indicating dirty slip rings and maybe the brushes not riding in the center of the rings. To gain access to the brushes and slip rings is a couple of hours on your knees, the left end of the enclosure has to come off, muffler, cooling fan must be removed with a puller. nothing real rocket science but labor intensive. One other test you can do before making a decision on the tear-down - under the control cover you will see two square aluminum potted modules, they are about 4 inches square. The one on the right is the voltage regulator with 6 connectors, a very small adjustment screw and a red LED. Find that and get back with us.
Quote
78buckshot
The post about the ATS got lost in the time I was writing, the transfer coils are energized with 240 volts ac, the top coil is fed from utility voltage, the bottom coil is fed from generator voltage so if the generator has no output then it can't shift the switch to the emergency position. You can run the generator without any control wires and if it's working correctly will have output but you may not have battery charging.
Quote
cirruspilot
I know exactly where they are.  In face the other day I did a minor adjustment to the VR because it was about 8 volts low.  It was no problem to adjust and of course there was perfect output at that time.
Quote
78buckshot
One of the wires is marked #4, it's the same #4 that goes down to the brushes, use a small jumper wire with alligator clips long enough to run from the #4 wire terminal down to the positive post of the battery. Clip it on the #4 wire, start the engine in manual, clip the other end of the jumper to the positive battery post and read the voltage at the input of the circuit breaker. Should see 175 - 195 volts line to line.
Quote
cirruspilot
Am I supposed to disconnect the #4 wire and jump it or....add the small jumper cable to the #4 wire while it is still connected?
Quote
cirruspilot
I owe you my utmost apologies.  After looking for the number 4 wire, I discovered two disconnected wires from the V-R that must have happened during my VR adjustment but I know I checked the voltage after the adjustment so my mind is numb.
But the bottom line is that the generator is functioning properly.  My last test tomorrow will be to pull the main house breakers and let the generator do it’s job.
Thank you soooo much for your help with this.
Sincerely
Don (Naples Fl).  Stay Safe!
Quote
Peddler
Based on the ohm readings on the 0 & 4 wire I would clean the slip rings.  If the resistance is high it can cause the DPE breaker to open temporarily which would create a no voltage situation.  I'm not saying it won't work but the readings indicate dirty/oily slip rings.
Quote
78buckshot
No need for apologies, glad we could get some results, if you have any other problems we'll be here.
Quote