Mep 005a TWC queston

[BMinor9968]

I have a mep 005a. Got it running, producing power, also converted it to single phase as shown in the YouTube video over a year ago. I have started it about once a month for the past year. Never had any issues with it starting or producing power. Yesterday i started it and noticed it wasn't producing power so I held the start switch up for about 10 seconds after initial start up. It started producing power, running 60 Hz, but dropped back to 0 after I let off the start switch. I started looking over things thinking may be a squrrel or bird my have damaged some of the wiring. I noticed the TWC (Thermal Watt Converter) behind the control panel was oozing black tar like googh. I'm guess this is probably the best place to start is by replacing it? Thanks Bernard

 

[Sephirothq]

What is your voltage reading?

 

[BMinor9968]

Correction: no hertz showing on the gauge or voltage unless start switch is held in the start positon after starting. While doing this hertz is right at 60 and voltage is showing less than 200 as it once showed 240. As soon as it's released hertz pegs out then goes straigh to zero and voltage just drops to zero. Thanks Bernard

 

[Guyfang]

First thing to do is find a thermal watt converter. In the meantime, start the set. Keep the S1 in the start position. Thumb up the S7, let go of S1 and see if it keeps running right, and if you have any idiot lights on. That way you can rule out faulty safety relays. The starting process over rides your safety circuits. The converter (with maybe a short circuit in it) might be telling the short circuit relay to not allow the set to run.

 

[BMinor9968]

Sorry I'm new to these gensets. By s7 you talking about the battle short?

 

[Guyfang]

Roger. Battle short. There is a wire diagram on one of the doors where you can look up stuff like this. Do you have all the manuals downloaded?

 

[BMinor9968]

Ok. Started it up. Let off S1 after it started and flipped S2. Still no change in volts (went to 0 volts as soon as I let off S1 same with hertz meter). No wiring diagram on any of the doors I did download all the TMs when I got it

 

[BMinor9968]

No idiot lights. I did test them by the test switch. All working properly

 

[Guyfang]

The troubleshooting in the -34 manual is a good place to start. Sounds like you have a static exciter problem. The volt regulator is in the same box as the exciter. If what I am writing about is Greek to you, start to read in the -34 manual. It's getting close to midnight her, and this old soldier needs to sleep. So get smart about this stuff and maybe someone else will jump in here in the meantime.

 

[BMinor9968]

I really appreciate your help. You well know and we'll respected on here. On last question. What is oozing out thermal watt converter? Why did It do that old age? Thanks

 

[Guyfang]

That goop starts to run out when the component fails. Something burned up inside. When the goo is solid, it keeps the components inside from vibrating. Has nothing to do with age, and doesn't always happen when the converter fails. Test procedures are in the TM. The converter was a fairly robust component. Rarely went bad.

The wire diagrams are suposed to be on the side doors, when they are open. If yours are missing, it because they probably fell off. The plates were riveted on, with aluminum rivets. The vibrations wore them out. The plates hang down or fall off. The plates are a good reference, but not to be fully trusted. There are several mistakes on them. For best results, use the TM's.

When looking this part up in the Parts TM, you will notice that it is listed twice. By looking at the UOC, usable on code, you will see that the NSN 6625-00-003-0973, (part number 69-589-1 or 268086) is the proper one for your gen set. You can use this NSN in your browser to find one. BUT, the NSN has been updated. That's because the old ones were not quite up to snuff. Or that the army wanted a converter that could be used in more then one type of gen set. So the army bought an updated one. You can still use the old style converter. The new NSN is 6625-01-180-7579, (part number 69-589). This part will fit the 15,30 and 60 KW gen sets. These are the only NSNs you can use. There are several others, that LOOK like the right part, but are for 400 hertz gen sets. That's the reason for the UOC. Org cost was $228.00

.

 

[BMinor9968]

I found one on ebay b4and new for $139.00. It is the new NSN 6625-01-180-7579 (part number 69-589). I have started reading the TM and will replace the static exciter if necessary when I cross that bridge. Again I really appreciate all your help and will keep you posted on the progress of the repairs and hopefully this thread with help others in the future!! Thanks buddy

 

[BMinor9968]

I found one on ebay b4and new for $139.00. It is the new NSN 6625-01-180-7579 (part number 69-589). I have started reading the TM and will replace the static exciter if necessary when I cross that bridge. Again I really appreciate all your help and will keep you posted on the progress of the repairs and hopefully this thread with help others in the future!! Thanks buddy

Part came in. Installed it and guess What? Everything is working just as it should. Hertz meter is reading 60 where I had the throttle adjusted at, and voltage is reading correct. Thanks for all your help Guyfang and I hope others will find this post helpful. If anyone has to replace the thermal watt converter pay close attention to the wires. Make sure you label them according to the letter and number on the TWC. There are 2 terminals that have 2 wires and the rest have 1.

 

[Guyfang]

Good job partner!!

It's also a good idea to always take the time to compare the wires on the thermal watt converter, to the schematic, if the set is new to you. It can always happen, that someone else has miss wired something. And if you just re-wire something just like you found it. Well, it's still wrong. NEVER trust some one else's work. Check it.

Once again, good work.