Disconnecting Battery of MEP-002A or MEP-003A While Running: Damage?

[Triple Jim]

Crawdaddy, I'd very much appreciate it if you could send it here. I'll pay the postage, of course. I'll PM you my address.

I don't need to unpot the electronics, but I do need the unit to get dimensions and bolt pattern. Is the unit exactly the same for the 016B and 701A?

 

[Crawdaddy]

It is the same between the 016B and the 701A, since the 701A is just a 016B with the ASK kit. I think there's other models that use the same regulator, but I can't think of them off-hand.

 

[steelypip]

The 701A is the same set as the MEP-016B. Unfortunately, I can't find a rated output for the charging stator in any of the TMs I have. It's single phase and little. As it used a 4HN battery and has a 7.5 amp DC circuit breaker, I'd guess that anything you can cook up for the MEP-002/003 should work.

 

[Isaac-1]

There is a ebay seller for now that has the new style MEP-016B charging regulator, you can look it up on ebay by the NSN 2920-01-282-8522 as it is poorly listed. The original is in also potted in a cast aluminum heat sink with fins, the new one looks very different in a machined aluminum heat sink with no fins, they both just have the same bolt spacing. One annoying thing about the new style is the holes are threaded where the original is not making it harder to install (I changed mine out a couple of years ago for one of these new style units). As I recall it is held in by 2 screws.

 

[Triple Jim]

I won't be able to match that price, so I'm not sure I could add anything to the situation other than a warranty. Why do threads make it harder to install? Is it easier to use through bolts?

 

[Isaac-1]

My concern is that this ebay seller seems to be the only source for this part, and who knows how many they have on hand or how long they will be available. I forget the exact issue with the threaded holes, it has been a couple of years, but I seem to remember issue with it binding when threading into the cabinet.

 

[rustystud]

Thanks Ike.



Your questions are appreciated. No Guinea pigs will be harmed if I can help it. I've been asked by several people on the board to make 24V regulators available. The reasons given to me include the high price and high failure rate of the originals. If I'm going to design one, I want to know of any shortcomings of the originals so I can try to build one that doesn't have them.

I don't know why anyone would want to disconnect the battery with the generator running, but I remember at least one guy who was trying to jump start his MEP-002A/3A. If my memory is correct, the battery was very dead, acting about like not having one at all, and when the owner disconnected the jumper cables, problems surfaced. I just don't remember the details.

That was my MEP-002A Jim. I was running the unit when the battery cable came loose, since I was just testing it and didn't take the time to tighten the clamp properly. I know sloppy work. Just as Doghead said the capacitor blew on the main fuel pump, and the circuit breaker blew. After finding out what damage I did, I just cut out the capacitor and it has run fine ever since.

 

[rustystud]

Jim,

If you decide to make a regulator, and I pray to God that you will. Please make it relatively inexpensive, beefier than the OEM and maybe at least a 10 amp regulator. If the stator would handle it, which I think it might, it would allow for faster charging. I read somewhere that with the 6 amp charging system currently in use, you need something like 4 hours of run time to replenish the drain just from starting the generator.

The 4 hour time came out of a PS magazine article. I have it somewhere. The soldiers where replacing batteries at an extremely high rate.

 

[Keith_J]

Leaving batteries connected on these sets will drain them, something in the voltage regulator puts a small parasitic load on the system. When the batteries are connected, there is a considerable spark like a capacitor charging. This will ruin batteries, I remember a PS article covering this with recommendation of disconnecting the batteries if being stored for more than a few days.

 

[doghead]

I installed a battery disconnect for that reason.

 

[CDR]

I leave my batteries connected and typical run once a month never had an issue

 

[steelypip]

I went the next level of paranoia and the batteries live in the nice, warm garage next to the house and get rotated weekly onto the Battery Tender for top up. It makes the MEP-002A that much perkier to start when it's really cold, although sweeping the snow off the battery mounts and hooking up the cables isn't my favorite chore.

 

[Triple Jim]

I got a test version of the 24V regulator in my 003A today and it works well. While the generator was running, I disconnected the battery and let it run for around 1/2 an hour. Everything continued to work normally, and the AC ripple was only about 65 millivolts RMS, thanks to the big capacitor in the regulator. As soon as I get some test hours on a couple units, I'll make them available. I expect this will be in two or three weeks.

Thanks again to everyone who provided information in this thread.

 

[doghead]

Sounds very promising! Any pics of this regulator?

Is this something easily changed by untrained monkeys?

 

[Triple Jim]

Ha, it would be a drop-in job if the wires didn't have to be soldered to the fuse holder. I put a couple bullet connectors on mine so I can change them quickly when testing. Here are a couple photos:

 

[Jimc]

thats awesome jim. glad you decided to do this. i know many including myself have been asking for quite a long time. as usual it looks quite professional and im sure the inside is done to the same detail. i actually might need one for my 002. i have to dig into it a little bit and do some troubleshooting.

 

[Isaac-1]

Looks great Jim, I too can't wait to order one to add to the spare parts kit.

 

[Triple Jim]

Thanks Ike. Like I always say though, put the new one in service and take advantage of the 2-year warranty. Keep the original for the spare.

 

[LuckyDog]

Jim,

Will post your product announcement in this thread?

<Subscribed>

 

[Triple Jim]

Sure, thanks for asking.