MEP-804a Voltage Fluctuation

[dijital357]

Good afternoon, long time lurker as a guest, new member and first post.

My name is Doug. About a month ago I purchased a non-generating 804a for a decent price for residential backup. Searching around on this forum helped me figure out what was wrong - failed voltage regulator. $180 for a brand new one and got it going.

A qualified electrician helped me work up a plan to add a second panel to my house to utilize all 3 legs of this triple phase unit. We hooked it up on only 2 legs to give it a test. Immediately halted the project because I have a lot of flicker out of my lights. Even on 2 legs it runs all my 240 loads (5 ton a/c and well pump) with no issue - like it doesn’t even know it’s there. But the lights flicker. We had the voltage set at about 125 volts to give us close to 220v combined phase voltage. I noticed the voltage fluctuates only about 6 tenths of a volt. But enough to cause flicker. Hertz measurement is dead on at 60 and barely moves even a hundredth of a hertz.

So I came back here and did some searching - found a few threads about the R2 potentiometer having a dead spot in it. So I turned the voltage down to 110v - voltage stayed extremely steady - and only ran my lighting circuits - works perfectly. Turn it back up to 125, it fluctuates, and they flicker.
I ordered up a new potentiometer for R2 - same deal. Tons of flicker. Frustrating.

Any ideas?

thank you,
Doug

 

[kloppk]

Are your lights LED's?
I have all LED lighting and some will flicker if the power to them isn't absolutely perfect.

 

[dijital357]

Are your lights LED's?
I have all LED lighting and some will flicker if the power to them isn't absolutely perfect.

Some are, some are not. Even the Incandescents flicker

 

[peapvp]

This is the absolute beauty of Chinese electrical engineering……..
EMC or electromagnetic compliance, radiated and conducted emissions and susceptibility are not easily translated into a 4000 year old variety of dialects…..
that goes for anything hooked up to the two L’s and N including the VR
In true Chinese tradition, one could try to install a large AC motor capacitor between the N and Ground Terminal on the Generator, since you probably got your bonding in your Utility Meter unit and removed Genset bonding.
Bonding in Chinese electrical installations involving Chinese made generators including Chinese made VR’s is something to be marveled at and is far beyond westerns minds capability to comprehend……

cheers

Peter

 

[peapvp]

@Guyfang are they giving you enough beer over there in the Vaterland or did they cut your beer allowance?

 

[Guyfang]

Me and a few friends who all bought into a beer brewery. Me, bottom row, second from left. I get all the beer I want!


Sudhaus. Where all the action is.

 

[peapvp]

View attachment 895231
Me and a few friends who all bought into a beer brewery. Me, bottom row, second from left. I get all the beer I want!

View attachment 895229
Sudhaus. Where all the action is.
View attachment 895230

@Guyfang, yes, I can see it clearly now! I will put in a phone call to the towns orderly and have them get the paddy wagon and Irish Tuxedo ready..,..,

 

[Chainbreaker]

@Guyfang, yes, I can see it clearly now! I will put in a phone call to the towns orderly and have them get the paddy wagon and Irish Tuxedo ready..,..,

Found this video... Where's Waldo... errr, I mean Guyfang? Perhaps in the restroom...?

Kommunbrauerei Burgkunstadt eG - Das sagen die Mitglieder - YouTube

My limited Jr. High class German has faded as I can't understand a word they are saying, or they've all had too much suds for me to translate! Regardless, its Sunday here & a good entertainment break... But now, back to your regularly scheduled troubleshooting of the gentleman's 804A.

Edit: I turned on the online translator & it seems the brewery got the "1059" appendage to its name in honor of the town's most prominent consumer "Herr Guyfang" who always showed up at that time each morning! Well, there could be some translation errors but seems plausible...

 

[dijital357]

Spent some time over the last couple days checking connections inside the control panel. Also took the cover off the big TB1 box in the high voltage panel and checked connections inside it.
I found a guide on another thread to set the potentiometers on the governor control - none of that made any difference.
I also attempted to use the same guide to set the reactive current potentiometer - ended up finding that it was cracked - bought a new one and soldered it in. I don’t like the one I got because it’s not the same as the factory part - but the actual specs on it are identical. No difference of course.
I checked pins 1 and 3 on the A1 voltage regulator - from what I’ve read this is the actual exciter voltage. Interestingly it fluctuates in exactly the same cadence as the output voltage does. I detached the wires and checked the resistance of the exciter - 34 ohms.
So I am starting to wonder if this new old stock voltage regulator is a piece of junk.

 

[dijital357]

Update to this saga - after all that it was indeed my new old stock voltage regulator. Replaced and it works completely fine. Whole house is running on only 2 legs right now. Voltage is perfect. A/C , well pump, etc running. Zero flicker.

I want to give a shout out to member @kloppk . He reached out to me and patiently discussed the situation. I purchased one of his voltage regulator kits. He shipped it here fast (2 days). Fixed.

Hopefully this thread will help someone somewhere along the way!

thank you all
Douglas

 

[loosegravel]

Update to this saga - after all that it was indeed my new old stock voltage regulator. Replaced and it works completely fine. Whole house is running on only 2 legs right now. Voltage is perfect. A/C , well pump, etc running. Zero flicker.

I want to give a shout out to member @kloppk . He reached out to me and patiently discussed the situation. I purchased one of his voltage regulator kits. He shipped it here fast (2 days). Fixed.

Hopefully this thread will help someone somewhere along the way!

thank you all
Douglas

Great guy! He got me straightened out on a 804B a while back. Same experience as you. Lightening fast shipping and great support on the installation process.