Engine governors...

[BioHazard]

Looks like I'm moving into a new shop with natural gas available...my next project is to build the cogenerator I've been dreaming about for years out of an inline 3, 4, or 6 engine. The biggest obsticle in my mind is coming up with some sort of speed control for a former car engine.

This is the kind of governor I'd like to use:
http://cgi.ebay.com/Hoof-BD939E-Mechanical-Governor-Onan-/290561814328?pt=LH_DefaultDomain_0&hash=item43a6d56f38

But at $400, that's not going to happen. That's more than I plan on spending on the engine. This and a couple others on ebay for the same price are all I have been able to find. My google searches have come up mostly empty.

So, my question is, is there a more affordable way to control engine speed? Something electronic, maybe? I know some of you have car engine based generators, how do you control the speed?

I also found this on ebay, but I'm more confused about how it works:
http://cgi.ebay.com/Electronic-Engine-Speed-Control-Governor-PER-ESD5520E-/280709184682?pt=LH_DefaultDomain_0&hash=item415b923caa
Would that do what I want? What would I use to actuate the throttle?

[Tom Reed]

You could try a cruse control. You might even find an engine with one on it.

[WStayton]

BioHazard:

  Check out the thread "Mercedes OM616 Control Unit" in the sub-forum "Automation, Controllers and Regulators".

  There is an electronic unit available from the  Generac Company that electonically controls the frequency, sensing the 60 cycle current you are making.

  The total cost for the computer and the actuator was $202.11 including shipping.

  I am still a few months away from setting eveything up, so I can't tell you how it will work, but since it was designed to manage a generator I would THINK that it would be superior to a cruise control for the purpose.

  I like the fact that it sensed current frequency, so it didn't care what the drive ratio of your set-up was, since I may have to use a transmission in 3rd gear to allow my engine to produce the full 24 kW of my generator.

  I also like the fact that the actuator was electric, since vacuum from a diesel engine requires some sort of add-on and, on Mercedes engines, at least, these units have been a head-ache.  On your natural gas engine you can just use manifold vacuum, so this feature doesn't really matter to you.

  I toyed with the idea of using a cruise control until I found the Generac unit, but cruise control units have a couple of problems:  1)  Selecting a precise speed is difficult - you have to fiddle with it until you get the engine to EXACTLY the speed you want before you activate it and 2) most cruise control units only allow you to "adjust" the speed up of down in discrete steps of a 100 rpm or so, which is way more than the tolerance of + / - 1 Hz that you want for AC.

  The Generac unit is SUPPOSED to take the engine exactly to 60 Hz when engaged, no matter what speed you engage it at - again that is heresay, I have no actual experience, yet, to be able to tell you whether or not it ACTUALLY works!  <grin>

  Also, since the unit is digital, there is no offset - it maintains 60 HZ, exactly, no matter what load your are generating, where an analog cruise control has a built in off set, so the more current you generate, the lower the frequency it maintains.  Having said that, however, more modern cruise control units are also digital, but many of them run off of the vehicle's computer that controls the engine, so you are stuck with trying to "kludge" a component into a job it wasn't designed for, if you use one of the newer ones.

  Hope this helped - its way less than $400, at least! <smile>

Regardz,

Wayne Stayton

[WStayton]

BioHazard:

  Geeze, I must be getting senile - I had two things I wanted to say and I forgot one of them!  <smile>

  The Electronic-Engine-Speed-Control-Governor-PER-ESD5520E that you reference is a Cummins part and would, I think, do a very good job.  The only problem is that it requires a proprietary actuator, either an ADC225-12V for a 12 Volt DC system or a ADC225-24V for a 24 Volt DC system.  The problem is that the cheapest that I was ever able to find one of these was something over $200, which brings the price of the package, with shipping to something in the vicinity of $350 - which choked me, too - especialy since I only paid $250 for my engine!!! <grin>

  The Cummins unit is a great unit and has functions in places that I never realized that generators had places, but it is more expensive than the Generac unit I referenced previously.

  I THINK that trying to use any actuator other than what the unit is designed to use is apt to be an exercise in frustration since your potential to have problems is far greater than your potential to have everything work flawlessly when you plug together a component from manufacturere A with a component from manufacturer B that were never envisioned working together.  Can SOMEBODY make it work?  Yes, definately!  Will you be happy trying to make it work?  I'd bet against it, especially if, like me, your first thought was a fly-ball governor!!!  <grin>


  My opinion, which is worth exactly what you paid for it!  <smile>

Regardz,

Wayne Stayton

[BioHazard]

I'd bet against it, especially if, like me, your first thought was a fly-ball governor!!!  <grin>

If only I could find something like that to work! 

I do like the sound of the Generac unit, where did you buy it exactly? Not having the extra belt drive or vacuum source seems like it would be more efficient. I want to keep electronics to a minimum on this machine, since I'm a lot better fixing mechanical stuff...but this sounds like a good place to make an exception.

[WStayton]

BioHazard:

  I too would prefer a fly-ball governor, but cheap and easy won out!  Both me AND the solution!  <grin>

  I bought the Generac parts from:

   Schwalm, Inc.
   13784 Monte Vista Avenue
   Chino, CA 9170

  Their website is anyrvparts.com

  The Speed Controller Stepper Motor is part # 092059 for $38.99.
  The Stepper Motor Kit (Really the "brains") is part # 098647A for $149.99.
  They charged me $14.13 for shipping

  Those parts, or slightly different flavors of them, are available at several different places on the web, but these guys were the cheapest by about $50 when all was said and done - of course I bought them in May of this year, so EVERTHING may have changed by now!  <grin>

  The set-up seems to be pretty comprehensive, with features like the ability to have the stepper motor rotate in either direction depending on what you need for throttle actuation, etc., etc.

  The instructions that came with it are pretty rudimentary, though.  Basically it just says to wire as shown, with an On-Off switch, if desired and adjust as required!

  See the previously quoted posting for a source for slightly more instructions.

  Connections to electricity are very basic, just +12 V, ground and 60 Hz sense.  I figured even a Mechanical Engineer, like me. could hook up three color coded wires and not make too many mistakes!

  Hope this helps!

Regardz,

Wayne Stayton

[WStayton]

BioHazard:

  About the thought that the electrical unit will use less power than a vacuum unit:

  I'm not sure that is strictly true - if you have any way to slightly enrichen the mixture to compensate for the additional air taken in through the vacuum to drive a vacuum unit, you will probably make gains, not losses, since the pumping efficiency of the engine is improved with lower, albeit only slightly, intake vacuum.

  I was surprised to discover that if you took a conventional engine and installed EGR on it, and then tested it on a dyno, presuming that you don't exceed the misfire rate of EGR, the efficiency actually improves, just because it is running against lower manifold vacuum.  The combustion with EGR is less efficient, but the less manifold vacuum due to a wider throttle angle for the same output power more than makes up for it.  If you advance the spark to MBT with EGR, it does even better!  However, you can only get something like 85% of the no EGR max power.

  With the electric unit, you will have an increased alternator load to drive the thing so the best you can hope for is a slight loss of total available power.

   Probably far more than you had any interest in knowing about the power output of spark ignition engines, huh?  <grin>

  Again, worth exactly what you paid for it - nothing! <smile>

Regardz,

Wayne Stayton

[BioHazard]

Probably far more than you had any interest in knowing about the power output of spark ignition engines, huh?  <grin>

By all means, keep it coming!  I am actually very interested in making my natural gas engine as efficient as it can POSSIBLY be. Always have been interested in getting a sparky tuned just perfect....

I should decide on an engine first though. 

Does anybody know of a nice heavy IRON 2 cylinder, water cooled engine? Basically I want the multi-cylinder listeroid of gas....

[Apogee]

Bio,

This is what I'd be buying...

http://rover.ebay.com/rover/0/e11030.m43.l1123/7?euid=1c65f2f9850446bc8f73ac140f7ec2d0&loc=http%3A%2F%2Fcgi.ebay.com%2Fws%2FeBayISAPI.dll%3FViewItem%26item%3D180448183293%26ssPageName%3DADME%3AB%3AEF%3AUS%3A1123

Steve

[BioHazard]

Bio,

This is what I'd be buying...

http://rover.ebay.com/rover/0/e11030.m43.l1123/7?euid=1c65f2f9850446bc8f73ac140f7ec2d0&loc=http%3A%2F%2Fcgi.ebay.com%2Fws%2FeBayISAPI.dll%3FViewItem%26item%3D180448183293%26ssPageName%3DADME%3AB%3AEF%3AUS%3A1123

That's a neat little motor, but is it water cooled? Any idea what the displacement or horsepower is? I was going to say shipping would be the killer, but it probably won't cost much more than a governor would....

[Derb]

Hi Bio. If you wish to do the job for nothing and have plenty of time and a little bit of nouse, use a vacumn unit off a cruise control system hooked up to the throttle using an adjustable tension spring. Use an old school carby type engine with standard distributor (non-computer) for simplicity. Good luck boss.

[deeiche]

SNIP
I should decide on an engine first though.  

Does anybody know of a nice heavy IRON 2 cylinder, water cooled engine? Basically I want the multi-cylinder listeroid of gas....

not 2 cylinder, but definitely heavy iron
Witte 15 Hp model C oilfeild engine
unfortunately freight would probably kill you

[WStayton]

BioHazard:

  " . . . dreaming about for years out of an inline 3, 4, or 6 engine"

  Let's take a look at this from an output point of view.  How many kW do you want/need to be able to make???  Then work backwards to what is apropriate for that output.  If you're looking for 2 kW and we're all thinking 20 kW, our suggestions are going to ALL be way off the mark!

  I could suggest a Ford 300 CID industrial 6 cylinder engine and if you hooked it up to your 2 kW ST head, you would be VERY unhappy, long term, even though it is a pretty good engine for SOME jobs!

  More input, please!!!

Regardz,

Wayne Stayton

[WStayton]

About Governors/Speed-Control:

  There are really two different "types" you can pick from, depending on what you want.

  If you want 60 Hz +/- 5 Hz for a 2 kW generator head, almost anythig with will work - rubberbands, screen door springs, automotive analog speed control, etc., etc.

  If you want 60 Hz +/- 0.01 Hz, grid tied, you need something more technologically sophisticated.  Solid state is ALMOST mandatory in this case, because any sort of analog device has droop in that you have to be OFF of the set point in order to generate a restoring force and the restoring force for an analog device is proportional to how much you are off of the set point.

  So, if you have a 10 kW generator and use an analog device and set it for 60.000 Hz at 5 kW, it will be running at higher frequency any time that demand is less than 5 kW and lower frequency any time the demand is more than 5 kW, no matter what you do, short of re-adjusting the set point every time the load changes.

  How much it will be off of the set point is another question entirely, and depends on lots of things, one of which is the cost, which USUALLY reflects the precision of the unit.  A $0.25 rubber band is going to drop/increase a couple of Hz per kW above and below the set point.  A Hoff flyball governor will be something more like 0.10 Hz per kW off of set point and other analog devices will be somewhere in between.

  If you are not that "electronic experimenter" type, who during his mis-spent youth was building circuits and designing electric chairs (!!) I think that you will find adapting an automotive cruise control to be a less than fullfilling task - but only you can make an accurate decision about what your interests and capabilities are.  Having fiddled with an automotive speed control, albeit NOT for a genertor, I have a minimal frame of reference - it seemed like everything that I did to fix a problem, and there were lots of them, made a new problem that was only discovered after doing a bunch of soldering/re-wiring/machining/welding.  In the end, the speed control only sort-of worked, and was NEVER what I would term an unqualified success!  The experience is what made me very cautious when looking for some sort of speed control for my generator set-up - having been-there/done-that with one that wasn't very good, I have no interest in repeating the experience.

  Also, I am a firm believer in using something for a given job that was designed for that job - again, shoveling snow with an ensilage fork just doesn't make sense, even if you can make it work, AFTER welding sheet metal between the tines!!!  By the time you account for the time spent welding the tines, if your time is worth ANYTHING, you could have bought the right tool!!!

  My thoughts which, as usual, are worth exactly what you paid for them!  <grin>

Regardz,

Wayne Stayton

[BioHazard]

BioHazard:

  " . . . dreaming about for years out of an inline 3, 4, or 6 engine"

  Let's take a look at this from an output point of view.  How many kW do you want/need to be able to make???  Then work backwards to what is apropriate for that output.  If you're looking for 2 kW and we're all thinking 20 kW, our suggestions are going to ALL be way off the mark!

Well, I'm getting a bit ahead of myself here. I'd better wait until I at least get the keys for the new place!  Basically my engine is going to be the heater for my 4,000sq ft warehouse + office. Electricity is only a byproduct. I only want to run it during what the utility calls peak hours and store up enough hot water for the whole day. I'm thinking something like a 20-25kw gen head, but I don't know yet. I also want it to run shop tools like an air compressor, welder, whatever else I come up with.....