MEP-002A Woes

[rjbguns00]

I tried the long detailed version but when I hit "post" I was told I was not logged in.

Here's the short version;

Unit seemed to work fine with no load. Pinched a wire to the shutoff switch with the oil filter can.

Now it only shows to gen 120 volts.

What's wrong?

 

[Speddmon]

I have to assume you fixed the wire?

The only wires around the oil filter canister should have absolutely nothing to do with generation.

Try checking the little "Remember Me" box under where you log in and it will not kick you off next time. I say this because we're going to need more information than jut saying it only produces 120 volts what's wrong.

 

[rjbguns00]

Thx for the tip.

Ok, I've read tons of the TMs and traced lots of wire. Couple of things I've found. The wire running from A1-1 to K1-6 was rubbing on the K1 socket mounting screw and shows signs of arcing. Checking the resistance of diode CR1 . Tm says + on A1-5 and - on A1-6 should show high resistance. This one tests reverse. I know it must be a typo but the wire chart/diagram shows a contradiction. Chart says P55L goes to TB4-12 and P55R goes to TB4-11. Diagram shows reverse. (-12 Change 5)

TM-34 Change 6 says to isolate the trouble to gen or regulator by putting a 12v battery in place of the regulator. Since it is generating 120v I think the next step is to test the diodes on the rotating rectifier. Seems like a lot of trouble so I thought I'd try this. Heeeeeeellllllp!

What else do you need to know?

And, Yes I fixed the wire.

CORRECTION; CR1 tests correctly CR2 tests reverse

 

[PeterD]

When doing tests such as diode checks, you must use the exact meter specified. Some meters reverse the lead polarity in the ohms (ohms have no polarity, but diodes do, and meters do...) So it is possible that the reading is opposite from what the manual says it should be.

For a diode test, low resistance one way, very high the other way. If you use a digital meter, you must use the diode test function, not ohms as the normal ohms test on a digital meter doesn't provide enough voltage to make the diode conduct properly. Read the manual for your meter for more details on how to test diodes.

 

[Speddmon]

Let's start off with a few simple things and forget about the TM's for a few.

Did you fix the wire you said you pinched and also the one you said was rubbing through?

I think you said the set worked fine until you pinched a wire in your first post? Did you actually test the functions of the set or did it "seem" to work OK?

What positions do you have the large re-connection switch set at, as well as the small volt/amp/phase selector switch on the control panel. Try changing the position of the large reconnect switch a few times and then returning it to whatever position you normally run the set in. Also, if using the set in any single phase mode, the smaller control panel switch should be rotated completely to the right. Either of the final 2 positions are the single phase modes.

have you been checking your 120 volts at the output lugs with a multimeter or have you just been going by the voltage meter on the control panel?

Can you adjust the 120 volts at all using the voltage adjustment rheostat on the control panel?

Let me know what the set is doing in the above questions and that will give me a better starting point.

 

[rjbguns00]

Peter,

I have 2 basic meters. (cheap) One has a diode setting but the manual says not for specialty ones such as zener diodes. It is digital and only shows OL on the low res. test. I don't have the manual for the other one (analog) but it reads opposite than the one w/ the diode setting. However it shows CR1 to have high resistance one way and none the other way. CR2 shows high and low. Either way the TM says + on a1-5 for cr1 and + on a1-7 for cr2. This makes cr2 read low with the digital.

 

[rjbguns00]

Speddmon,

I fixed the wire I pinched but I have only pulled the rubbed wire away from the screw for now. It tests good for continuity. I was going to do that when I replaced the diode.

No I didn't actually test the functions. Only plugged a grinder into the 120 outlet to verify power. The AC volt gauge showed 220 and the volt adjust would move it quite a bit + & -.

The large switch is set to the left 120/208 3ph and the control panel switch is at about 1 0'clock. Marked from top to bottom 3, L3-L0, L3. (the way it was set when I first saw it. I think we did run it once at the 11 0'clock pos.) I have tried switching the large switch thru all positions to see if there might be an issue. (per TM, and no it wasn't running when I moved the switch) This unit belongs to a friend and I have no idea if he will ever use 3 ph but since it should be capable I'd like to make it so. I don't really like the idea of checking the voltage on the output lugs (hate getting shocked) so I haven't read up on how to do that.

It's been a while since I ran it and have the A1 relay block out (waiting on the diodes to get here) but the volt adjust didn't seem to change the voltage much. I'll try it tomorrow and let you know for sure as well as the results of the output lug tests. Thx

 

[Speddmon]

I'm more confused now than before. How did you have 240 volts showing on the panel meter when it is set to run in 120/208 3 phase? The most you should get is 208. But since the small switch on the control panel is set to show the voltage from L3 to L0 then you should only read 120 volts. Even with the small switch set at the 11 o'clock position you would only show 208 volts because it is reading from L3 to L1.

As far as checking the voltage at the output lugs goes. Just touch the meter leads to the lugs VERY CAREFULLY while the main breaker is on and you can read the voltage from any combination of the lugs

 

[rjbguns00]

Spedd,

Sorry for the confusion. You should know by now that my forte is not electricity. I don't think I said it produced 240 but it (the gauge) would show 208 and would go up to 220 easily via the volt adjust control. I feel better knowing it should only show 120 on the current settings. I'm curious as to why it showed that before. Ran it several times. At least 6 or 8.

I'm going to guess that the large switch should be to the rt setting 120/240 1ph to read 220 on the gauge.

You lost me on the L3 L0 and L3 L1 lingo. Guess I'm in for some more reading.

 

[Speddmon]

Only plugged a grinder into the 120 outlet to verify power. The AC volt gauge showed 220 and the volt adjust would move it quite a bit + & -.

That's the part that threw me off. 220 and being able to move it + and - quite a bit equates to 240 volts (Since it's a common mis-statement for 220 / 240 volts) It would have been better to say 208 and able to adjust up to 220....but I digress...LOL

It probably showed 208 volts before because you had the small selector switch set to read voltage across any 2 phases rather than from any phase to L0.

And as far as the L1, L2, L3 and L0 lingo. That is the descriptions of the phases of the output voltage. Since it is 3 phase, you have 3 "lines" of power coming from your generator. They are L1 (Line 1), L2 (Line 2), L3 (Line 3), the 4th one not mentioned is the neutral L0. If you open the cover hiding the output terminals of the generator to the side of the control box, you will see the markings L1, L2, L3 and L0 formed into the fiberglass mounting plate the lugs are attached to.

Try this if you see this post today.

Set the large switch on the 120/240 single phase setting. Set the small selector switch on the panel to roughly the 2:00 o'clock position (Reading from top to bottom 1, L3-L1 and L3) That tells you you are monitoring the generator in single phase mode, reading voltage from L3 to L1 and getting your current reading from L3. If the generator works properly you should see 240 volts on the volt gauge and be able to adjust it down below 240 and above 240 I'm going to guess at least 10 volts or more each way.

 

[rjbguns00]

Thanks for the info Speddmon. I'll try the 120/240 1 ph setting when I get time this pm.

Also, should the volt adjust knob have much affect on the 120v in the 3 phase setting?

 

[Speddmon]

Yes, it will adjust the voltage no matter what the configuration of the generator is.

 

[Speddmon]

after you try it this afternoon/evening, let us know the results of the test and we can then start to figure out what might be wrong with it.

 

[rjbguns00]

Try this if you see this post today.

Set the large switch on the 120/240 single phase setting. Set the small selector switch on the panel to roughly the 2:00 o'clock position (Reading from top to bottom 1, L3-L1 and L3) That tells you you are monitoring the generator in single phase mode, reading voltage from L3 to L1 and getting your current reading from L3. If the generator works properly you should see 240 volts on the volt gauge and be able to adjust it down below 240 and above 240 I'm going to guess at least 10 volts or more each way.


I followed your instructions and everything checks out. The voltage meter reads a little lower than actual voltage on the lugs. Initially I adjusted the gauge to 240 and read 250+ on the lugs. After turning it down to about 230 it read 240 on the lugs and L0-L1 and L0- L3 read 120.

Going to set it back to 3 phase and test again.

 

[rjbguns00]

The 3 phase tests as it should. 120 on all their lugs and 208 on theirs. Didn't test the low end but cranked up the lugs read 135 and 235.

I'm still wondering why the AC Volt meter showed 220 every time it ran before I cut the shutoff switch wire.

 

[Speddmon]

Sounds like the generator is working fine. As far as the voltmeter, probably a faulty meter. Find a replacement. It's obviously reading higher than it should.

I would not waste my time replacing working diodes. Tape up the suspect wire that was rubbing through and enjoy the generator

 

[rjbguns00]

Thanks for all the help Speddmon. I did insulate the wire and the spare diodes will be there if someone needs them.

Now for the rat killing.

The TM says to disconnect the battery cables if it is going to sit for more than 2 weeks. I suggested putting a switch like on a Deuce to make it easy. Would that be a bad idea?

Also, he has a solar charger that he wants to install. I am concerned about mounting the solar panel on the ask cover because of vibration. Will that be a problem? I can make a bracket from the skid up the back but getting it high enough for full sun unsupported may vibrate pretty bad as well.

 

[bmwsyc]

I have a disconnect on my batteries for my 002a. The disconnect is on the battery post connector and looks like a (green) twist knob. I open up the disconnect when I'm not using the generator, and it works fine for starting and such...no problem passing adequate current.

 

[Speddmon]

The TM says to disconnect the battery cables if it is going to sit for more than 2 weeks. I suggested putting a switch like on a Deuce to make it easy. Would that be a bad idea?

Not a bad idea at all. It the charging regulator were going bad or the capacitor were to short out, that would keep it from draining the batteries.

Also, he has a solar charger that he wants to install. I am concerned about mounting the solar panel on the ask cover because of vibration. Will that be a problem? I can make a bracket from the skid up the back but getting it high enough for full sun unsupported may vibrate pretty bad as well.

Since the solar panel has no moving parts, is a sealed unit and all the joints in them are soldered I don't think the vibration would do much damage to it, if any.

 

[rjbguns00]

Great!! Thanks for all the help & info guys. I really apperciate it. I love this site!!!