MEP-003A Governor not compensating for load.

[leedawg]

Hello ive been a long time lurker here but decided id go ahead and make a post because i have a question. Ive had my MEP-003a for about 8 years and till about two years ago had never read about anybody else having one sure was great to run across this board.

Any way my question I guess is more of an operational question, I have noticed that my unit whenever I put it under load obviously the motor drops a bit in rpm due to the greater demands on the generator head. Well this seemed normal and I always compensate by giving it a bit more throttle till its back and 60hz. Well after reading on these forums for awhile and the TM it sounds as though the governor is supposed to make this throttle compensation automatic. THe dip is usually only about 3-4 hz not that big a deal but it bugs me. And obviously when some of the demands are turned off the motor runs faster that 60hz. So I took the liberty of shooting some video of this and wanted some feedback from you guys that own either a 002a or a 003a to let me know if you experience the same sort of operation out of your unit. I did try adjusting the governor per the TM with the ratching dip adjustment I spun it all the way as far as it would go clockwise so the spring was all the way at the top of the arm. All it seemed to do was make my base speed faster and require me to move the hand throttle all the way to idle to keep the rpm at 60 hz but same dip in hz under load. Perhaps I did the adjustment wrong I just put it back to where it was originally and it operates the same as it always had. Is this operation normal? Or is my governor not doing its job? I apologize in advance for the crappy quality of the videos but its good enough to demonstrate what is going on, I took two of them one shot further out so you can see the percent load gauge as well as hz and one close up on the hz. Thanks in advance for the feedback and help really appreciate it.


[media]http://www.youtube.com/watch?v=Lxlx-AVgj4c[/media]

[media]http://www.youtube.com/watch?v=9vxZaupfmJA[/media]

 

[rosco]

Bump

 

[storeman]

bump

 

[AceHigh]

Mine is about the same.

 

[Carl_in_NH]

You say there's a 3-4 Hz dip - but the video only shows about 1.5 Hz; that's pretty normal at 1-2 Hz. It's a mechanical system, and therefore not a perfect return to 60 Hz as an electrical one might be able to establish - but pretty darn close. It should pose no operational problems for backup power - and I suspect anything else you might pick up for a backup genset will have about the same frequency control performance (unless you go to a unit with all-electronic control).

 

[jbk]

set your droop with a load closer to max. i see the meter only around 40 or 50%. i adjust mine with 80 to 100% load and i hit all at once (open and close the breaker). adust the rachet until it starts to surge(hunt) and then turn it until it stops. get yourself somthing digital to monitor the freq. also check your valves to make sure your eng. is tip top. jim

 

[doghead]

I have found several mep's that have had the spring(on the adjuster) drop a notch. This caused slight "hunting" with load. Might try looking at that.

I simply put the spring up one groove and use a ty-wrap to hold it there.

Not exactly what I see in your video, but close.

Mine run more steady than your is(less speed/hz change), with switching loads

 

[leedawg]

Awsome thanks so much guys Yeah upon looking at the graduations of the meter I guess its not really a 1-2 hz drop seeing as the bottom is 55 and the top is 65. I guess I thought it would hold it rock solid right on 60hz ive never seen it adversly affect anything that is being powered by the unit while its running. I might have to check the spring on the ratcething mechanism see if it jumped down a notch. I am going to have to figure out how to pose a greater load on it to adjust the load droop better, ive just been using the load of the house to do it but from reading on here ive noticed people use heating elements and such to simulate a load. I will also go put my fluke meter on it to see the hz its putting out I assumed the guage on the panel would be fairly accurate perhaps its not though. Thanks again for all the responses though and having a look.

Lee

 

[Isaac-1]

As a general rule of thumb mechanical governors on generators are only good for a range of about 2.5 - 3 hz from no load to full load. You can tune them closer than this, but will still see drift in this range with temperature changes, etc. Rock solid (+/- .25 hz) requires an electronic governor, even then large loads hitting at once can drag the engine down. For commercial units with mechanical governors the general advice is to set them at about 62 hz, this way they will average close to 60 hz at load.

Ike

 

[Speddmon]

What Ike suggested with setting it at 62 Hz is about as good as you are going to get it for the old mechanical governors. That's what I do, I run it unloaded at about 61 to 62 Hz and when it's fully loaded it drops down to between 59 and 60.

From what I saw of your first video and the % load meter, I would be more inclined to start cheking valve adjustments and make sure the motor is in proper order like someone mentioned earlier in the thread. I only saw your meter bumping up to about 25% load or so (maybe I was off, but it didn't look like it moved that much); and with that light of a load on it you really shouldn't have seen much change in frequency at all, if any. Mine only drops the 2 to 3 Hz under a full 80% resistive load.

 

[refloyd]

When we still used these units in the Marine Corps they all did the same thing. It does this because these generators do not have a precise governor on them. The governor that is on them will compensate for small changes in the load, for everything else you have to manually throttle the engine up with the cable. Even the Mep-803a that replaced this unit has the same utility governor adjustment on it. Out of all the generators I have worked on in my time in the mep-003a was one of the most hated just behind the mep-016b.

 

[doghead]

Could you tell us a few things about the Mep-003 that you did not like, and why?

 

[Speddmon]

Could you tell us a few things about the Mep-003 that you did not like, and why?

I'm curious about this myself, simply because I love mine. For it's simplicity and ease of use and repair, I think it's wonderful. Please elaborate.

 

[DieselBob]

I'm curious about this myself, simply because I love mine. For it's simplicity and ease of use and repair, I think it's wonderful. Please elaborate.

 

[refloyd]

Well a few of the things that I disliked about these were the noise from them, of course I never seen one with the sound dampening housing. I did not like having to work on this unit. We always had problems with the battery charging circuits. Also had problems with the mufflers breaking off due to the vibration of the unit. The rest of the problems we had with these was due to operator error, (not checking everything properly before operation). Had lost of fires due to wiring chaffing and rubbing trough in various places inder the controll cubicle. I have also seen them catch on fire in the output box (area right below loadstuds) due to rats and things like that.

A couple of the good things about these units are the durabilty of the main generator itself, and the master control switches. If I had it my way the Marine Corps would still be running all of the older generators still.

 

[leedawg]

Thanks for all the responses glad to know my unit is operating "normally" within the limits of the mechanical governer.

However the post above has given me all kinds of new problems to be worried about potentially happening. These things have mufflers could have fooled me. I'm going to have to go out and check all the wire harnesses and reconnection box make sure its all clean in there, don't want an electrical fire. I can't imagine hating this unit I actually rather love mine it runs like a top and has never not started or produced power when I've needed it over the last 8 years.

refloyd is there anything else you recall being a real negative on these units? Why just the 003 id think the 002 would be just as hated its practically the same unit with half the motor missing

Thanks again for all the responses.

Lee

 

[storeman]

I'm hoping in advance that I love mine!
Can't wait to get home and work on them once it warms up.

​

 

[refloyd]

Well the reason I have only taalked about the negatives of the 003a is because we dont use the 002a in the USMC, but the negatives would be exactly the same . I honestly think you would be fine with either one just make sure you check all the wiring and everything real good. (as long as you dont run it all day everyday for weeks on end, thats when enginges and main generators start failing). Even as much as I hate them I would still get one just for emergency power for huricane season(would monitor all of the things that I know to be problems though).

 

[Tilliscon]

I am having the same problem with hunting but mine is doing it unloaded.when I put a 50 percent load on it the hertz crash to 55 and I have to bring the throttle up to adjust it.when I remove the load the throttle spikes to 65 hertz I'm new to the mep002a any ideas were to start.thanks

 

[LuckyDog]

... any ideas were to start.thanks

TM 5-6115-584-34
Section 7-3.

You can find the manual (TM) on this site.