Homebuilt genset...

[gumpy]

Ok. I've had a Thermoking engine and genset head for a few years with the intention of building my own genset. I've never taken the time to do this. Maybe this spring.

So, a couple questions. 

1. Does anyone know where I can source pulleys for the set? I will need tripple groove sets in a specific ratio, something like 2100 RPM on the engine, and 3600 RPM on the head.

2. Does anyone know who else has built their own generator and do you have contact information?  I know I've seen a few who did this, but Greg Bush is the only name I can remember. Does anyone have contact info for Greg?

craig

[Paladin]

I have some links on the subject, someone who was also making the pulleys on a special order basis. I found a place that sold pulleys for go carts and such but can't find the link at the moment.  I was thinking of going with direct connection via couplers.
I'm trying to locate all of the info but here is part of what I have:

http://www.mikeholt.com/forum/Forum1/HTML/002287.html

http://www.geoduck.com/epicenter/order.cgi?page=power_sources_generators_and_batteries.html&cart_id=%%cart_id%%

[TomCat]

Craig,

You may find what you need starting on page 1026 at www.McMaster.com

Jay
87 SaftLiner

[TomC]

Grainger has pulleys too.  Would suggest running the engine at 1800-will be quieter.  Then a simple 1:2 ratio will be needed.  Good Luck, TomC

[Paul]

Try Browning Mfg in Maysville, Kentucky.  They will have a distributor in your area. browning is part of the Emerson Power Transmission.  www.emerson-ept.com   There is a lot of help on this site. Use their locator to find a distributor close.

     Paul
     www.incredibus.com

[rv_safetyman]

Hi Craig.

One of the better sources for both the belts and pulleys is:  https://www.motionindustries.com.  They will have more than one branch in your area. 

You will want to use what the industry calls "narrow" industrial belts (3V/3VX).  That product line does not have as many belt sizes as the "classical" industrial belts (B/BX), but they have higher ratings and are made of more heat resistant material.  When you get closer to putting the package together, drop me a note and I will help you design the drive (balance the sheave combination with belt length to get the center distance you want, plus make sure you have enough capacity).  If you choose to work directly with a vendor to design the drive (not many offer that service any more), do not get too concerned about the published belt ratings (they are based on 25K hours ratings). 

Going with 3V/3VX belts will mean that you will be using pulleys that are mounted on the shaft with tapered bushings (two different systems) and that is a good thing. 

Also, you will need a speed control system that will assure controlled 60 HZ power. 

Bob Belter (same name in the member list) has done almost exactly what you are doing.  He used a belt driven head and a VW diesel engine.  Just looked at it this past week at the Eagle Rally.  He can tell you what controller he used.  He also has made a very quiet enclosure that sandwiches plywood/lead sheet/roof felt.

One last consideration, be sure that the head is capable of having the radial shaft load that will be created by the belt drive.  Some are only designed to be direct driven.  I suspect the engine you have will not have the same issue.  Many of those units used belt drives and the rear main was designed to handle the radial loads.

Jim

[Ncbob]

Craig, it would be helpful to know if the engine was governed at a specific speed to run the compressor in it's original configuration.  My guess would be that the Engineers would have designed the package so that the engine ran at it's best torque/horsepower curve.  This would be an ideal point to work from and select your pulleys accordingly. Something tells me that you've already done that since you refer to the 2100 RPM point.

My other concern is the HP of the engine.  It takes 1.36 HP to create 1 KW of power. If these numbers fall in line with your numbers...you're in.

Another factor which would concern me would be the droop factor of the existing governor. That would determine the engine's ability to absorb applied loads and recover to governed speed without too much delay. Normally we would not switch off each load circuit before switching to 'Generator'...we'd just flip the switch and hope the genset could absorb the load. That's where the governor droop and acceleration rate of the engine come into play.

Guess I've given you enough ideas to think about. I have no doubt that when you finish you'll have exactly what you want.

Bob

[Kristinsgrandpa]

   Craig, my brother built a genset from an Isuzu C-201 Thermo King  engine and a 10 KW head. He might be able to help you some.

He used double belt pulleys, but a triple would be better.

He has no problems with HZ/RPM without a controller. Maybe the governor is that precise, I don't know. I believe he set the speed at 60.5 HZ, no load, and with everything in the coach running it stays on 60HZ. 
My brothers is set up for 1400 RPM but that is too low, mine runs at 1800 RPM with a 15 KW head with no problem at all.  So I agree with Tom C, 1800 RPM is about right.

Boogiethecat has a good source  for votage regulators.  He will probably chime in here with some info.

I have the name, address and model no. written down somewhere if he doesn't pop in on this. Its very reasonably priced.

I have a Thermo King with a C 201 also, but it is direct drive with an Ohno head on it. I got mine from a man in Arthur, Il that runs a generator build/rebuild shop. If you have any trouble with the Thermo-king he can help tremendously.

He copied his manual and sent me a copy.  My brother also has a different manual (a better one) that he copied for me. 

The man in IL, Lloyd Dean, told me that he has seen C-201 engines go over 100,000 hours with just occasional rings and bearings replaced. They have tungsten carbide cylinder sleeves.

I'll have my brother contact you if you want, and can also give you Lloyd Deans phone no.

Ed.

[gumpy]

Ed,

Yes, please have your brother email me his contact info and Lloyd Dean's info, also.

This sounds exactly like what i'm going to do. That's the engine I have. I talked to Greg Bush this morning about his. He used a 3 belt pulley system on his. I'll probably do that.

Greg said his governor was just fine. Maintains frequency well.

I was thinking I had read something that said the engine was set up for 2100, but that may not be the case. 1800 is probably correct. That's what Greg set his at, too. It's been a while since I looked at this stuff. I have redesigned the Thermoking reefer starting system so that I should be able to start it with a single switch, or have my inverter start it. I think I'll try to build that this winter and get it ready.

craig

[gus]

Craig,


For best engine efficiency try to set your engine speed at the max torque speed and adjust the gen required rpms with your pulleys.

You may not have enough HP at max torque speed but this is best if you do. You can easily find out by using the HP/torque curves available for most engines.

[Bob Belter]

Ahoy, Bus Folk,

Yah, I did a genset creation based on a VW engine and a 12KW dynamo.

I got the Gillette dynamo almost 20 years ago.    I got the VW diesel engine about the same time.  Back then, there were few good gensets in the market, and a 12KW unit would about take up a complete bed of a pickup truck.
The Gillette dynamo was 12KW 120/240 VAC – two pole 3600 RPM.  The VW diesel was quiet and of low weight.  My package is quite compact.

Belt drive for the dynamo.  There are excellent comments above for the belt drive pulleys and belts.  In my case, the diesel engine runs about 2100 RPM.

The governor system for the genset is a Woodward electronic device.  A model 4500 controller @ $ 225.00, plus an actuator @ $170.00.  Berge's Generator Service   310  830 4592 .  Good outfit, and the unit is about good enough to run an electric clock.

Box for the genset is composed of a layer of ½" birch plywood, two layers of ordinary roofer's 30# felt, one layer of 2 lb/sq/ft roofer's lead, two layers of roofer's felt, and finally, one layer of ½" birch plywood.  Labyrinths for air flow in and out. 

Mufflers are two cheap Kragen 1 1/2" units , plus a glass pack return.  Exhaust is out the top.  Working OK with about 175 hrs, and not carboned-up.  Cheap and easy to replace if they clog.

I had planned to include some sound absorbent material inside the box, but it is so quiet as-is, that if anyone else is running a genset, you cannot hear mine.

BTW, Gillette is still in business, and the present dynamos are double wound, so that you can draw 80 % of your load off one phase.  Superb stuff, and eliminates a lot of concern about "balanced loads".  They must cost about six-bits more than the other dynamos, because none of the bus conversion purveyors of gensets offer them.     

All in all, quite successful.

Enjoy  /s/  Bob

[dparker]

all,

FWIW - diesel engines are typically metered fuel device (ie injector pumps, metered gear pump) or cam valved to the injector in the case of the 2 stroke dd -- these provides for fairly exact speed control especially in constant speed/load applications.  For most genset this is adequate -- you can have 30 RPM's of deviation before it even makes one Hz difference ... (60 hz x 30 = 1800 rpms) this does not matter to most things in coach who really cares if your blower motor runs at 1800 RPMs or 1770 (59 hz), resistive loads (heating elements) are not affected and power supplies don't care as they are looking to just smooth out the oscillations and make dc anyway ... the woodward control is nice unit and is common on gensets of all sizes -- more sophisticated governors utilize PMG control which is a permanent magnet excitation which is tied electronically to the injector pump to allow the genset to more quickly accept and shed load based on changing current conditions (load which requires more or less fuel to maintain the same speed/frequency) to provide a more stable rotation = frequency control under changing conditions --  the more rotational mass you have which is nearly proportional to the KW capacity the less the speed/frequency of the genset will change --- what gets really tough is large gaseous fuel genset 400KW+ that use natural gas or propane since the fuel is not metered -- frequency control is tough when the system is not steady state -- woodward makes these and they work pretty well -- so a woodward for a diesel is easy -- the point to all this run on is ... if you have a genset that is 15 KW and your largest load that can change is 3.5 KW heater then mechanical controlled governor that came on the genset will probably be more than adequate -- but if you are using a 5K genset on motor that pulls 2.5 KW running (more than is recommended but will work) then pmg controlled regulation will increase the response time and better maintain frequency...

good luck -- sounds like a neat project -- i know that you document it well -- i have couple of the units that are placed on the container dollies to provide power to refrigerated containers but they are 480 volt 3 phase -- but like someone indicated those little diesel engines seem to run forever --

i bought a 20 kw genset on a slide -- i wished i would have spent the extra dollars and remote the radiator -- i would have baffled the genset compartment to change the small amount air to prevent residual heat buildup (like on inboard motor boat) since most of the heat would pass out of the radiator in different location-- in this way the genset would be as quite outside the bus as in -- we provide generators (big ones 250 KW+) for concerts, tv productions. etc these units are baffled in this manner (even though they pass the same air through the unit that is used for radiator cooling) i would then have the genset radiator changing air from the exterior of the bus in the back engine compartment above the muffler -- you might even do two fans electric and reverse the flow in the winter time to maintain some heat in the bus engine compartment ...

btw ... when i am at these events i am amazed at how loud the diesel gensets on those high $ prevost entertainer coaches are to the exterior -- they are quite inside but loud on the exterior -- you would think that if are spending 800K + that you would spend 2K more to make the genset quite on the exterior

d-

[rv_safetyman]

Craig, I was messing with my photos from Quartzsite and saw that I had taken a photo of Bob Belter's generator installation.

Jim

[gumpy]

Yeah, I wish I could see one in person.

I've got a line on a local company that might be able to help me with the pulleys.
I'm working on the starting circuitry design now, and hope to start wiring that up this weekend. I thought it was
going to warm up here, but it turned around again, so won't be able to start on the engine for awhile. Also, I might
be going back to work soon, so that may put a crimp in my fun, too.

[TomC]

Watch out for the cheapo 3600rpm gen heads.  I know of one gen company that was using some made in Italy, that on a 4,000 watt genset for a boat, when a 30 amp load was put on the gen, the heat coming out of the gen vents was almost hot enough to burn you.  Whereas on my Powertech 10kw (Marathon brushless), I have put a 9,000 watt load on it and also felt the air coming out of the gen vents, and it was just a little bit warm.  Excess heat produced when generating a load is a sign of whether a generator has efficient windings and clearances.  If your genset puts out too much heat when generating, your wasting engine energy to overcome the cheapo windings on the generator-which ultimately means burning more fuel to create the same amount of electricity.  Good Luck, TomC