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Milbank Generator

11K views 15 replies 6 participants last post by  nrp3 
#1 ·
We have installed 3 Milbank Generators 10 kw ,and on two of them we occasionally get an overspeed error code.Checked the gas pressure(manometer) and rpm (tiny tach)and hrtz all readings fall within spec.Last power outage this summer the generator started up fine and quit after about 4 hours ,overspeed error.The overspeed error as I understand can relate to "underspeed" like lack of proper fuel pressure.I am going today to run tests on the unit with the help of a company rep.Has any one else had any trouble with an overspeed error code on the milbank generators?
 
#3 ·
Generator overspeed

Having read your post, I have a similar problem with a 40 KW Honeywell
(Carrier) brand generator actually manufactured by Generac. This unit is probably 7+ years old with a Ford 3.9 liter water cooled engine. We did not install this unit originally.
We are experiencing overspeed shutdown in a few seconds, although sometimes after 10+ minutes. This unit also indicated a low oil pressure shutdown once.
Voltage and freq. checks show normal. Believe that the problem lies
with the speed sensor (magnetic pickup), the board receiving and processing the various signals or possibly the generator voltage regulator, all difficult to check and too expensive in price to be guessing. Does anyone have
experience with this problem or this particular genset and could enlighten. Any help would be greatly appreciated. Thanks
 
#4 ·
Just got back from checking out the unit , under a load of 47 amps (rated lp at 41.7) the unit ran fine about 57 hertz and 3400 rpm with an excessive load.Turned on the gas furnace and the manometer read 11.7 with full load and gas furnace running.Never kicked out.Checked stator and armature wires checked out fine cold and after running a while .5 ohms on stator and 13 ohms on armature .Load of 20 amps 3650 rpm and 60 hertz, no load 62.5 hertz and 3750 rpm.Couldn't find a thing wrong ,Last time I said the same thing and lost it after 4 hrs of running(lucky the job is close to home).Told the homeowner I would be back in a month and test it under load one more time.No idea what caused it to fail as it worked like a charm today.Looked for loose wires carbon marks ,none to be found.Everything in its proper parameters.Makes me nervous as the homeowner is gone looses power and his house would freeze up this winter?:blink:
 
#8 ·
I don't mean to offend, but it sounds like the unit is running on propane. It has been my experience that the units are shipped set for natural gas. Was the propane conversion done? The larger orifice associated with natural gas may account for the overspeed condition as it would allow more fuel and hence higher speed. Once again no offense intended.
 
#9 ·
No offense taken as I am here to learn and no matter how long I've been in the trade there is alway something new.The unit did ship for NG but there is a wiring harness that must be connected if it is going to be used with LP as I understand by connecting the harness which is clearly labeled to connect if to be used with LP,will electronically switch the orifice to LP.We did connect these wires for LP at the installation.At no load the speed is within parameters of the Genny specs(3750)
 
#10 ·
We are trying to come up with a reason that these two units don't have bad governors (or other part) and are quickly running out of options.

The only thing I have left is that a few years ago I was installing Eaton generators pretty regularly and had two bad jumper plugs like you were describing. Out of eight generators two were bad, the wires had been installed in the wrong holes.


The fact that it is intermittent leads me to believe it's a governor. How long have these units been installed, and has the problem always been there?
 
#11 ·
yes maybe a bad plug in at the harness i did look at them but did not pull them apart,How would one go about testing that the orifice is is changing over?There are two brass adjustment screws on the orifice device,I guess that would be worth looking into.Maybe read up on that type of valve and look a little closer at the connections.It makes sense that if the connection was loose or bad that it would "choke "out the genny intermittently by switching back to NG.The units have been in about one year.
 
#16 ·
They are and Milbank generators are no longer sold. You may be able to go to Briggs and Stratton's website and enter model and serial numbers to get owners manuals or at least download and view them. I can log in and look things up on the dealer site and see most documentation.
 
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