MEP-003a No voltage

[Guyfang]

I think, and don't quote me on this, but I think that besides the wraps, the CB1 needs to be changed and R2 needs to be adjusted, then a 002A box can be used in a 003A gen set. Will look tonight when I can get at the TM's.

 

[juddspaintballs]

OK, sorry for the delay and thank you for those helping me along with my slow timeline of working on this.


I measured T1. 18.5 ohms on the primary windings and 1.6 ohms on the secondary. In spec.
I measured T2. Open on the primary windings, 18.5 ohms on the secondary. Bad.

I took apart T2 and found the solder joint to the H1 lead broken off of that very tiny little wire. I soldered it back on, but it didn't hold on long enough for me to wrap the transformer in tape without breaking again. I need a new one. Sending Ray70 a PM now.


The linear reactor is here as well as the stator for the DC charging system. As long as it remains dry, I'll pull the generator out of the run-in shed with the tractor and install those two parts at least. The LR might not be the reason why I don't have voltage right now, but it did test bad and I have a new one on hand, so I might as well replace it.

 

[Chainbreaker]

...I measured T2. Open on the primary windings, 18.5 ohms on the secondary. Bad.

I took apart T2 and found the solder joint to the H1 lead broken off of that very tiny little wire. I soldered it back on, but it didn't hold on long enough for me to wrap the transformer in tape without breaking again.

Yep, that was my hunch and why I suggested checking those 2 transformer's for a broken wire soldered to screw terminal tabs, that would certainly explain the high voltage reading and why it was intermittent. Glad you took the time to ohm them out and discovered that one was in fact bad. If you can't find a Mil Spec. replacement transformer there are other generic transformers meeting the specs that will work.

 

[juddspaintballs]

Hopefully Ray70 has what I need. Worst case, GMG has a NOS T2 on hand, though a bit pricey.

 

[juddspaintballs]

Ray70 is sending me T1 and T2 for a reasonable price. I did reattempt soldering my T2 back together again. I don't think it worked. I replaced the Linear Reactor. What a PITA! The old one actually had the plastic casing breaking apart on it. When I finally had it on the bench, I had an open circuit between terminals 1 and 2 instead of 14.6 ohms like it should have. 3/4 and 5/6 were both within 1.46 ohms of 14.6. Obviously the LR was bad as well.

 

[Guyfang]

I don't know what it is, but soldering transformer wires, even stator winding ends, has never worked for me. And I am a more then fair hand at soldering. It makes no difference if I use solder paste, or not. Never seems to work right.

 

[Ray70]

TI and T2 are in the mail headed your way. ETA, Thursday... Hopefully this gets your problems solved!

 

[Farmitall]

I don't know what it is, but soldering transformer wires, even stator winding ends, has never worked for me. And I am a more then fair hand at soldering. It makes no difference if I use solder paste, or not. Never seems to work right.

The varnish/ enamel has to be cleaned off the copper winding with an Exacto knife down to bare shiny copper, then tinned and twisted to the out going lead if possible, even one twist will usually hold.

 

[juddspaintballs]

USPS says there is a delay in the package containing T1 and T2. That stinks because I work Friday/Saturday for 48 hours, I'll be busy all day Sunday with family, and I'm working again Monday for 24 hours. I'm signed up for Tuesday overtime as well, but I might cancel that. So at best, I'll be able to install T2 on Tuesday. The suspense is killing me.


As a side note, is the blower of a MEP-002a the same as the MEP-003a? I think I need to swap out the magnets around my stator to see if that's why I don't have enough AC voltage from the stator for charging my batteries.

 

[jamawieb]

USPS says there is a delay in the package containing T1 and T2. That stinks because I work Friday/Saturday for 48 hours, I'll be busy all day Sunday with family, and I'm working again Monday for 24 hours. I'm signed up for Tuesday overtime as well, but I might cancel that. So at best, I'll be able to install T2 on Tuesday. The suspense is killing me.


As a side note, is the blower of a MEP-002a the same as the MEP-003a? I think I need to swap out the magnets around my stator to see if that's why I don't have enough AC voltage from the stator for charging my batteries.

Yes the blowers are the same on both models.

 

[Ray70]

What are you getting for AC voltage when you test the DC charging circuit? If by chance you end up needing a blower wheel.... I know where you can get one...
Let me know when the package arrives... So much for USPS 2 day delivery!

 

[juddspaintballs]

I'm getting about 26v AC from the stator. I replaced it with a NOS from Erik's with the same results. I cleaned up the magnets and no change. I may need your magnets, too. They separate from the blower at least.

 

[Triple Jim]

T2 supplies the regulator with a sample of the generator output voltage. If T2 doesn't have an output, the regulator will think the generator output is low and cut back its output to zero so no control current flows in CVT1. This should make the generator output go high if everything else is working right. Since the problem is no output, is seems that something else is wrong too.

 

[juddspaintballs]

Well, dang. I only worked 34 hours instead of 48, so when I got home this evening I installed the (tested good) T2 from Ray70. No output voltage, still. Back to the drawing board AKA starting at the beginning of this thread and testing everything again.


At this point, I've swapped for a NOS and tested good Linear Reactor, used and tested good T2 transformer, and a Triple Jim/Lakeland Voltage regulator.




Frustrating...

 

[Chainbreaker]

... No output voltage, still. Back to the drawing board AKA starting at the beginning of this thread and testing everything again.

Well we know that you have/had more than one problem. If you found a broken wire in T2 plus the Linear Reactor failed test and those components are now replaced you have another issue responsible for no output voltage.

Just to cover the bases...Have you exercised the "AC Voltage Reconnection Switch" several times? If it does not move easily you can open the side panel & then loosen the switch's screws that hold the wafers/switch contacts and spray in electrical contact cleaner and then exercise the switch.

 

[juddspaintballs]

I have exercised it several times prior to starting this thread thinking that could be it. It moves easily and I haven't touched it since starting this thread.

 

[Chainbreaker]

Just a thought...Haven't seen any mention of testing the "Rotating Diodes". If you do a search here using "Rotating Diodes MEP-003a" (Also MEP-002a) there are several good threads for symptoms of no AC output due to bad rotating diodes and testing of the 6 rotating diodes and how to replace them if required.

 

[Speddmon]

Just a thought...Haven't seen any mention of testing the "Rotating Diodes". If you do a search here using "Rotating Diodes MEP-003a" (Also MEP-002a) there are several good threads for symptoms of no AC output due to bad rotating diodes and testing of the 6 rotating diodes and how to replace them if required.

Doing the battery test (hooking a 12 volt source to the regulator) and having it generate voltage, as he has done earlier in the thread pretty much eliminated the rotating diodes. That test tells you the generator portion is fine. The problem lies in the control side.

 

[juddspaintballs]

That's what I thought, but I couldn't find where it said that in the manual this morning.

 

[Ray70]

Maybe we should revert back to the CVT1 test? I know you mentioned some readings were close, but not quite within spec. I'm not looking at the TM at the moment, but I believe you need to disconnect all the wires before measuring. Then, maybe telling us which pairs were off and by how far were they out? I'm not an expert on the CVT1 but did once have a "NO Voltage" problem that was caused by one of the CVT1 windings being off.