MEP-002a low output current

[jrcampbe]

Hi guys,

I tried to use my 002a and have a problem. The unit starts and runs just fine. When I had first bought it and set it up, there was a short at the starter positive lead against the shutter box. When I hooked up the batteries, the VR capacitor burned up and the ground strap burned. I replaced the cap and ground strap and fixed the short. That history may have something to do with my problems.

The unit shows 240V on the gauge, and I can adjust this with the voltage adjustment as expected, but I get almost no output current. I had it hooked to the house transfer box, and the most it would do is dimly light a few lightbulbs. I disconnected the cable to the house and tried testing the generator alone from the service outlets.

I plugged a big halogen work light into the AC service outlet and it lights dimly, like maybe a 40W incandescent bulb. The current meter stays down near zero.

Can you guys give me some suggestions as to what might be going on? Why can't I get any power? The voltmeter at 240V means the field is energized, correct? I tried flashing it with no luck.

Thanks in advance,

Jim

 

[Triple Jim]

Does the volt meter drop when you connect a load?

 

[jrcampbe]

No, it doesn't seem to.

 

[glassk]

what terminals are you using/testing and what is the switch position you have selected

 

[Triple Jim]

In that case, I'd look for a dirty/corroded/loose connection in the output wiring, or something wrong in the reconnect switch. If the meter is showing 240V even with dimly lit bulbs connected, you must have a high resistance along the way. With no load, do you have 120 from L0 to L1 and L0 to L3, and 240 from L1 to L3?

(started typing before glassk posted above... he asks good questions too.)

 

[glassk]

Picked it up here ,

Has a way of raising the Bar,..

 

[jrcampbe]

Thanks, guys! This makes sense.

The volt meter shows 240 when in the far right switch position, which I believe is L1-L3 voltage. Interestingly, it shows about zero in other positions (I think those are L1-L0 and L3-L0, correct?).

That would seem to imply the problem is on L0, right? Wouldn't the fact that the service outlets also don't work point to L0 as the culprit?

I have it connected with hot legs on L1, L3, neutral on L0. But shouldn't the service outlets produce power at 120V regardless? If so, that might imply the problem is before the interconnect switch? I don't know how the 120 outlets are wired, but it would seem they would be separate from the interconnect switch?

I'm going to take a look at the output wiring in about an hour.

Thanks for the tips, guys!

Jim

 

[jrcampbe]

I failed to answer one question: I have the switch on 120/240 single phase.

 

[glassk]

That short and wire melting may have got the reconnection switch contacts or something, now Jim has actually built some regulators and knows the steps in the TM to narrow it down. So Jim would be my Goto source for tips on checking while running and which sets of contacts inside the box, ect.

 

[steelandcanvas]

Just thought I would ask...is the unit running at 1800 RPMs?

 

[jrcampbe]

Hey guys, working on this now. It must be 1800 rpm (sounds like it), but also I can dial it in to a steady 60hz output frequency as measured by my multimeter.

i was wrong about the voltmeter switch. In the far right (L3-L0), I get a nice, steady 120V. Second from right (L3-L1) I get a steady 240V. I can dial this in perfectly using my multimeter and the voltage adjust. The other positions have no reading, although I think those are all 3 phase positions. So I have good voltage, good frequency, poor output current.

The output wiring *looks* good. No corrosion or broken wires or connectors. The reconnection switch is "spongy", I think due to an internal spring, but clicks solidly into position.

Any guidance? I was hoping to see something obvious in the output wiring, but I don't.

thanks again guys!

Jim

 

[jrcampbe]

Update: when I switch on the AC circuit breaker on the generator and turn on the house load, the current meter goes from zero to about 25%. The engine lugs slightly but voltage does not drop. Frequency drops about 2 Hz. Lights in the garage come on dimly.

I checked at the plug I connect to the transfer box and I have correct voltage there.

Jim

 

[Triple Jim]

You said when you connect a load, the voltage does not drop. Are you measuring this at the output lugs or looking at the panel meter? If it does not drop at the lugs, but your lights in the house are dim, something is wrong after the generator.

 

[jrcampbe]

I am looking at the meter on the front panel. Not very accurate, I know.

Also, keep in mind that the 120V outlets on the generator do not light a bulb to full brightness either.

I'm stuck...

 

[jrcampbe]

There is good continuity across the AC circuit breaker on all poles.

 

[jrcampbe]

Is there a continuity test I can do on the reconnection switch? Does that even make sense as the problem area?

 

[jrcampbe]

So I think this is definitely a generator problem and not a house wiring problem, because the AC outlets on the generator itself do not produce enough current to run a shop vacuum. It comes on, but doesn't have much suction. A shop light plugged in is dim.

Naturally, I waited to hook this up until I have an outage. I got it running and saw it produced electricity, but stupidly didn't load test it. Ah, those life lessons just keep coming.

Any more ideas you guys have for me are much appreciated!

Jim

 

[Triple Jim]

Looking at the schematic, if the front panel meter shows a steady 240V, you have that at the L1 and L3 terminals of the reconnect switch. What do you read by measuring the voltage at the main output lugs when you have a load between L0 and L1, and between L0 and L3? Those two voltages should be a steady 120V. Do they both drop with a load applied?

 

[jrcampbe]

Checking now. One more test: the service 120V outlets are dim regardless of the position of the reconnect switch (disconnected from lugs to test this).

Jim

 

[Triple Jim]

I'm wondering if you have a bad connection at or near terminal 6 of the reconnect switch. That becomes the neutral, L0, and if that were floating around, you'd always have 240 from L1 to L3, but trying to draw a 120 load would shove L0 (neutral) off center and you'd get less than 120 on that side, and more than 120 on the side without the load.