Mep 006 frequency gage pegs and shuts down the motor

[WILLYSOVERLAND]

ok I got a meter from harbor freight. I have 138 volts at idle, then the voltage goes up as the idle is increased. the frequency gage bounces from 1-3 and does seem to go up as the speed of the engine is increased. at one point it was at 6 which I think should be correct as the meter is a 20k hz meter. I took a photo of the overspeed control I will post it as soon as I figure out how.
JUST CHECKED MY NEW METER AT HOME, IT DOES THE SAME THING IN THE WALL SOCKET, IT ROLLS AROUND JUST LIKE IT DID ON THE GENSET. I AM GOING TO RETURN IT IN THE MORNING.

 

[WILLYSOVERLAND]

ok engine running, with hertz meter plugged into convenience outlet I had 45 hertz and 152 volts (at idle speed), after increasing the speed the hertz did not change but the voltage went up to about 168. the hz gage on the control panel was pegged and the volt meter was right on with the readings on the fluke meter. I had to use the battle short to speed up the machine and the over volt light was on as soon as I tried to speed up the machine. as always thanks in advance, and if there is anything I can do for anybody here just ask.

 

[Guyfang]

You having any luck on this set?

 

[WILLYSOVERLAND]

I was hoping you would reply. with engine running, with hertz meter plugged into convenience outlet I had 45 hertz and 152 volts (at idle speed), after increasing the speed the hertz did not change but the voltage went up to about 168. the hz gage on the control panel was pegged and the volt meter on the machine was right on with the readings on the fluke meter. I had to use the battle short to speed up the machine and the over volt light was on as soon as I tried to speed up the machine. when I turned the battle short switch the machine shut right down of course. thanks in advance

 

[Suprman]

Sorry didnt see. 152 volts at the conv outlet is wrong and 45hz is way too low. You are def over voltage. My best guess would be the voltage regulator. Why dont you take a look at the control panel and the voltage adjust potentiometer and see how that and its wiring look.
Will

 

[Guyfang]

This indeed sounds like a volt reg problem. Using the throttle adjustment cable you could not bring it over 45 hertz? Aside from the voltage problem, you should be able to get the hertz up higher. No, I take that back! The hertz reading is taken from the AC voltage output! So when you have 152 volts at the outlet, the hertz is not going to read right. Its way to high! You need to solve the overvoltage problem first.

And tell me, has this set EVER worked right in front of your eyes? Because I have seen a problem like this before. Someone installed a 400 hertz static exciter, (for a MEP-116A) in a 60 hertz, MEP-006A. Same symtoms. I also saw this when someone ordered a 400 hertz volt reg and installed it in a 60 hertz static exciter box. Look at the NSN and or part number on your static exciter box. Should be right under the two canon plugs. Then pull the static exciter out of the set, (about 8 bolts and two canon plugs) so you can pull the cover off. Check the vot reg out to see if its a 60 or 400 hertz volt reg. Check both the card and the chassis.

This sounds a lot more complicated then it is. Takes about 10 minutes to do. And, of course, the volt reg may be bad. Normally you will see burn spots on the volt reg card.

 

[WILLYSOVERLAND]

I have never seen this unit work untill after i got it home. It started pretty easy compared to some sets i have. The only problem i spotted when it came in was the cover was off the govener. The box on this machine was mounted under the shelf and water filled the gov box and rusted the 4 mounting bolts off. I replaced the gov box and still have the same problem. I swapped out the box with the overvoltage relays and reverse power relays i swappwed out the exciter box with three different ones and one was a new in the box. The only box i didnt swap out is the big square relay box with about 10 amphenol plugs going into it. I also changed the freq transducer box.
The only question i have is where is the voltage regulator ? Is that the card inside the exciter box? Or is it inside the control panel?
As always thank you

 

[Guyfang]

The volt reg was the in the static exciter. Its the chassis with the card on top. I would still make sure the part numbers correspond to the numbers in the parts TM, and don't forget to look at the UOC, Usable on Code.

The big box with all the canon plugs is the S/R, (Special Relay) Box.

Ah, a MEP-806A doesn't have a governor. So why don't you take a picture of it so I can know what you are talking about.

 

[WILLYSOVERLAND]

My machine is a mep006a here are the photos the first one is the exciter box brand new 50/60 hz i swapped this out with two others first. The first one was from a 30 kw 50/60 hz machine and nothing changed then i tried another one and the 24 volt circut breaker button popped out so then i purchased this new exciter box and still have the same issue. The tatical relay box was swapped out with another one from a used machine (30 kw50/60 hz) with no change and the last photo is the govener box i swapped out (i see now its the load govener box) tried a different load govener box and nothing changed. And one more thing i changed out the frequency transducer with no luck (i have 110 volts ac on one side and i think 24 volts dc on the other side.

 

[Guyfang]

OK, we are making progress here.

First off, the static exciter from a 30 KW, MEP-005A is not compatible to a MEP-006A. Looks almost the same, but have a completely different NSN and Part Number. So you can not use it to troubleshoot.

Where did you get the second Exciter? What is the Part number on the end of that exciter box. Is it also a 30 KW box? Or maybe a 400 hertz box?

If the excitor looks like its been opened, check that the volt regulator ALSO has the proper NSN and or Part Number. I once got a rebuild, that had a 60 hertz excitor, with a 400 hertz volt reg card in it.

Do you have the TM's available to check out the part numbers?

Correct NSN and Part Number for the static exciter, (MEP-006A) is:6115-00-244-1214 & Part number:70-1367
The first picture is of a correct Excitor.

The Tactical Relay Box is compatible between the two sets.

 

[WILLYSOVERLAND]

The exciter box in the photos was brand new in the sealed container right from the gov. Im glad its the right one. It was never tampered with.
Do you think i should try to change the special relay box? The only ones i have would come from 30 kw machines 50/60 hz. I only have one 60kw machine.
I have the manuals you posted online in this website. I spent a hour in the tm 5-6115-545-12 (1) manual and didnt see where you got the part numbers from. Sometimes i miss stuff right in front of me. One good thing is i always learn other stuff when i cant find what im looking for.
Are the overspeed actuators the same on 30 and 60 kw machines? Should i try swapping that out? Im good at changing parts but suck at diagnosing. Thanks again in advance

 

[Guyfang]

Morning!

Or maybe afternoon? Its 19:19 here.

Sadly, the SP relay boxes are not compatible. Lots of parts in them are interchangeable, but some are not.

When you want to look up parts, go to TM 5-6115-545-24P. That's what the P is for. To let you know its a parts manual. If you have never looked at it, you should take a half hour and look slowly through it to get a feel for what is what, and what is where.

The TM 5-6115-545-12 is the Operator's Manual. The Bible. In it, you can learn how everything operates, and how it interfaces with other things. Lots of good info there. It also has troubleshooting and explains how and what to do for minor repairs. The TM 5-6115-545-34 is for higher level repairs. The troubleshooting guide in it helps you with more complicated problems.

I looked up the speed switches in both the 30 and 60 KW gen sets. YES the speed switches are interchangeable.

Now, a little more explaining. When you look in the 30 KW parts manual, you will find that there are 4 DIFFERENT speed switches! How can that be? Well, the first two, are MECHANICAL switches. They are the old types. Not seen often. You can, in theory, fix them. But why TWO switch NSN's? Because there are several different types of gen set. So you HAVE to look up front, in the parts TM, for the, UOC, or Usable On Code. And because the MEP-005A and the MEP-114A are basicly the same set, but provide different voltage/hertz output, some parts are different. The UOC for the MEP-005, (60 hertz) is CLA. The UOC for the MEP-114A, (400 hertz) is CLC. When you look up/order parts, The UOC can kill you if you don't pay attention. The second two speed switches in the 30 KW manual are ELECTRICAL switches. Non-repairable, and also for a 60 hertz set, and a 400 hertz set. I used the 30 kw manuals for examples, simply because I had them open in front of me. The 6o KW manuals are set up the same way. So there are four speed switches listed in the manual.

Now, please look up in the 60 KW, MEP006A parts manual and tell me which speed switch, by NSN is supposed to go on your gen set. That way you and I will know you understood this long winded dissertation, and others who come after will also learn by reading it!

Then you are going to look at the speed switches you have, compare the part numbers to the part numbers in the book and tell me if you have the right ones!!

You are going to be a generator mech, when we are done here!

 

[WILLYSOVERLAND]

ok here goes. think I found the right code for my machine code a+d mep006a I found the speed switch on page 252 figure 90. going from my speed switch the part number is 70-1105-3 in the manual the sub sections are 1105-1,2 and 3. the nsn number I think is 5930-01-018-1888. I couldn't see how the part numbers match from the manual to the number on the part. so if the part was missing I never would have been able to get the right part or if the part was the wrong part somebody else installed I would be out of luck. the serial numbers in the figure 90 confused me too they had 4 sets of serial numbers two for the 400hz and 2 for the 60hz. my serial number is fz04714 which fell into the second set of serial numbers . I'm sure I am just missing some small bit of info that connects everything together. thank you for your time and patience. I am going to post a phot of my speed switch in case it helps somebody down the line. please ignore the first photo I do not know how to delete it.

 

[Guyfang]

ok here goes. think I found the right code for my machine code a+d mep006a I found the speed switch on page 252 figure 90. going from my speed switch the part number is 70-1105-3 in the manual the sub sections are 1105-1,2 and 3. the nsn number I think is 5930-01-018-1888. RIGHT!

I couldn't see how the part numbers match from the manual to the number on the part. You can also go to the back of the parts manual, to Section IV, National Stock number and Part Number Index. Look at the index. First it shows NSN's. Next to the NSN's is the figure and Item number. Farther on down the list, is Part Numbers. Next to the part number is figure and Item number. When trying to find out if a part number or NSN goes to your set, start here. If its not listed, chances are its not a part for your gen set. In your case, 70-1105-3 is listed as figure 90. No Item number, so that means its the whole part, not a repair part, to the speed switch.

so if the part was missing I never would have been able to get the right part Wrong. If its missing, you look in the parts manual for the part that is missing, and then look at the UOC, to find out which part you need.

or if the part was the wrong part somebody else installed I would be out of luck. Wrong. See above answer. If you want to see if its the wrong part, you look up the part number in Section IV to find out if it goes to your gen set, then look to see if it has a UOC, and if it fits your model.

the serial numbers in the figure 90 confused me too they had 4 sets of serial numbers two for the 400hz and 2 for the 60hz. my serial number is fz04714 which fell into the second set of serial numbers . Correct, but what that blurb means is that the electric speed switchs were first started to be used on those set when issued. Its not important to you at this time.

I'm sure I am just missing some small bit of info that connects everything together. You just need to work a bit more with the system and then it will fall into place.

thank you for your time and patience. I am going to post a phot of my speed switch in case it helps somebody down the line. please ignore the first photo I do not know how to delete it.

So, your speed switch, with a part number of: 70-1105-3, listed in Figure 90, Page 293, NSN: 5930-01-018-1888, with a UOC of: CF is made for a MEP-115A, a 400 Hertz gen set. Yours is a 60 Hertz gen set. So the speed switch is not the right one for your model.

 

[WILLYSOVERLAND]

So im trying to cross reference the parts numbers from a 30 kw to a 60 kw. To me the part numbers are the same but the nsn numbers are different. If the parts number is the same does that mean i can use the speed switch from a 30 kw on a 60 kw? The code on a 30 kw was cla-czn page 232 figure 61 in the parts manual for a mep005a. Thanks again for your time

 

[Guyfang]

Yes you can use the speed switch from a 30 KW, as long as it meant for a 60 Hertz machine. Look at the part number on the 30 KW speed switch, and then look in the book. What's it say?

 

[WILLYSOVERLAND]

3 parts machines and all of them are turned so the tag is in the back. The one on the 60 kw has a right hand turn and all the others go straight up. I am going to take one off thursday. I didnt have time to do it right today so it has to wait. I assume there is a notch like on a dodge distrubitor that turns the oil pump like on older cars.

 

[Guyfang]

They are all supposed to have the 90 degree adapter. But will work without.

 

[WILLYSOVERLAND]

thank you

 

[WILLYSOVERLAND]

This is a no progress update. I have several machines and all of them have the wrong speed switch. I tried running the machine with the speed switch un hooked, no warning lights on but no power either. I assume the speed switch flashes the field coils for the initial magnetism to begin. The over voltage light does not come on. Pretty sure this is my problem, now i just have to find the right part, that i can afford. As soon as i find a new or used part for my machine i will update this page. Even though im still not up and running i feel pretty good that i only have to change the speed switch and i think i will be ok. Thanks again