Cheaper to not buy it, expensive lesson if you already bought it. Unless you own a machine shop or otherwise have some resources, even putting a 60hz generator end on the same engine isn't going to be a snap.
Most engine sets have a one bearing generator mounted directly on the bellhousing with some sort of flexplate bolted to the flywheel etc. Most imported generators I have seen are 2 bearing, designed to be driven by a coupling from a shaft or belt driven maybe. Mating one up can be done, just not a bolt up job.
now if you can find a similar 60 hz set with a dead engine, or have a machinist buddy you're in business.
Coupla questions. The generators at Northern and
Harbor freight look a little light-weight, construction-
wise. Is it just the frame, or is the whole thing just
a happy homeowner version, similar to the Home Depot
offerings (i.e., low duty cycle, optimistic ratings)?
The 10/20 kW generators I am used to seeing are at
physically least twice as large as the ones shown.
Do they include any monitoring or control electronics?
(Details are sorta skimpy at their web sites).
Also....
Any anecdotes on using belt drive?
How many, what size, what types, lifetime, etc...
Just had a thunk. How about using toothed belts
(like a timing or blower belt) to keep two or more
generators in phase and paralleled.
Just read an article in Machine Design about high
horsepower toothed belts on dragsters, but it gave
no expected life.
<als>
Toothed belts are a great way to transmit power w/o slippage. They would be somewhat more expensive than V belts, but require less maintenance. Correctly sized, they will last almost indefinitely on a back-up generator. We use a machine with a "PolyChain GT" belt linking the PTO of a truck to the mixer body every day about 4 hrs running time and replace a belt only when it breaks every several years. I think some of the commercially produced PTO generators are using toothed belt drive now instead of gear box.
I doubt the regulators of the two small generators would appreciate the linkage even when you got them in phase.
Quote:
"I doubt the regulators of the two small generators would appreciate the linkage even when you got them in phase."
Oh? Why not? The only thing I can see is if the regulator
is capable of over-driving the field, or there is some
mismatch to an electronic governor. What do I not understand?
Be gentle. I have only had to replace defective parts in
regulators, not understand their use and/or behavior.
<als>
The easy way is to convert your home to 3 phase 400 cycle. Lighting is more efficient at 400 cycle.
The surplus store that sold you the generator might have other equipment that you could convert.
I know that electric coffee makers run at 400 cycles ( I put a few in Hueys).
Anything with a chopping power supply should work.
Refridgerators and mircowaves may be available that were used in airliners - allthough I think big airlines have 120/240 for such things.
Sometimes it cost a lot to save money.
I used a Gates Poly Belt with two cogged sheaves to hook my "2" bearing Northern generator to the prime mover. Works great! But you better make sure you have a way to adjust the angles between the prime and the gen so that the belt tracks correctly.
Wasn't reeeeal cheap. I bought one sheave used off the web and the other sheave new with the belt from Grainger<?>. Cost about 200 and change.
That generator is quite stout. Seems that the case is about 1" thick aluminum.
Conversely, I just cut up a naval generator (Onan?) that was 2.1" thick steel/iron housing. Weighed about 3000#. Sheesh! It was only a measly 5kW! 120~ ! Run by a 4 cylinder engine. Was quiet .. But pretty pointless.
I'm not the expert here, someone who knows about this better than me please jump in. I am interested in this as well.
The regulators on the two sets have to coordinate so one set doesn't hog all the load (current)while the other is relatively unloaded. If there were two drivers instead of one, the more heavily loaded driver would "droop" and help balance the load between the two generators. But you would have synchronization issues and possibly stability problems as well! With one driver on two generators, no synchronization issues, but the generator with the highest voltage at any point in time would take more of the load. I believe this could be so bad that one was run continuously at or above the "surge" capacity and damaged and the other be relatively unloaded the whole time.
Much cheaper and simpler just to get a large enough set to start with unless you just want to do it that way. If you could split the load up into 2 separate parts, then it would work more simply on the two generators.
Just curious, but how big is that 400Hz set? That 25kW generator on the website above at 120/240 single phase will run a pretty big house load. I was trying to figure if the armature field or stator of one of those 400hz sets could be rewound or reconnected and the governor adjusted to get 60Hz out of it. That would be turning lemons into lemonaide.
