MEP-003a Charging System - Higher Than Normal

[ckesey]

I have a MEP-003A that isn't charging the batteries. According to the testing article here (and TB) I have a bad regulator. I also had a open stator which has recently been replace.

After stator replacment, I'm getting 56v AC between the two stator wires while it's running (and wires disconnected from the terminal block) . The TB says 30-35v AC.

When I test the stator without it running (wires disconnected) I get 0.8ohms (close to the 0.6 in the TB test for being good.

The gen is dialed in at 1800 rpm and the main AC voltage is 122v on each leg. What would cause me to get this much output voltage on the charging stator?

 

[Triple Jim]

If I remember right, the 30-35 VAC is with the stator connected to a working regulator. When open circuited it can get higher.

When you measured 0.8 ohms, did you account for the meter lead resistance? Touch the leads together and read the resistance. Then subtract that value from the reading of the stator resistance.

 

[ckesey]

So there is 0.2 ohms in my test leads which puts this even closer to what the manual says is normal.

I checked and it says to conduct this test with the leads disconnected (open). I just don't want to kill a new rectifier if this isn't normal incoming voltage.

Looking at this I don't see how it can't be normal. What else is there? There is a magnet (that's visually appears to be in good shape) a stator which I just replaced with NOS that ohms out to what the manual reads and its turning at a fixed speed which results in 60.2 htz AC output voltage 120/240v (which would indicate the engine RPM is correct).

I guess I could put a aftermarket battery charger on it but I would really like to make it orginal.

Thanks for any input

 

[Triple Jim]

I doubt if there is anything abnormal going on. Maybe your meter is not a true RMS type.

 

[ckesey]

I'm using a Fluke 79 which says on the front it's a true RMS meter. I don't want to overthink this but I really don't want to set a match to $100 on hooking up a new rectifier to it either. I don't get any output on the current rectifier.

 

[Guyfang]

Are you sure its the right Stator? Did it come in the original package? Was the package closed and the right part # and NSN were on the box?

 

[ckesey]

I can't say for sure as the box and paperwork has been discarded. The purchase was for a 003a but can't say for sure that's what I received/installed.

This morning I purchased another as a spare that I'll installed and compare results.

There is simple and easier fix to charge the battery but I really want to retain it as orginal.

Thanks

 

[Guyfang]

Look at both Stators for a part number/NSN. This kind of thing happens, sometimes.