Eaton UPS' and Generator

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TheMannequin

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Hi all,

I finally took the plung and bought a 8.75kVa (7000W) MacAfric generator and got it installed.
Works like a charm during loadshedding, and can run the whole house with no issues.

On my router/ont/TV and unRaind Server I have a Eaton 5e 850va UPS connected (one for the server and one for the rest).
They also work 100's to keep thing running while I now switch over to the generator....BUT as soon as they receive generator power, they switch over to battery, and beep like they not getting any power from the outlet.

The electrician was here this mornig, checked the voltage comming out (224v) from the generator, and it's not overloading as even when the gesyser kicked in, load was only at 14,7 amps on it (wired for 32amps).

So....what I've read on the internets....it's seems the only way to 'fix' this is buying ONLINE UPS'.... surely there has to be a reason/fix as to why the UPS believes it's not getting the 'correct' power from the generator?

Any boffins that can explain this to me?
 
PaulMurkin said:
The frequency? Have you checked the frequency coming from the generator?
Click to expand...
Thought the same... but they couldn't test it.

Will it be that it's too high or to low causing it?
Adding more load to bring it down if too high maybe?
 
TheMannequin said:
Hi all,

I finally took the plung and bought a 8.75kVa (7000W) MacAfric generator and got it installed.
Works like a charm during loadshedding, and can run the whole house with no issues.

On my router/ont/TV and unRaind Server I have a Eaton 5e 850va UPS connected (one for the server and one for the rest).
They also work 100's to keep thing running while I now switch over to the generator....BUT as soon as they receive generator power, they switch over to battery, and beep like they not getting any power from the outlet.

The electrician was here this mornig, checked the voltage comming out (224v) from the generator, and it's not overloading as even when the gesyser kicked in, load was only at 14,7 amps on it (wired for 32amps).

So....what I've read on the internets....it's seems the only way to 'fix' this is buying ONLINE UPS'.... surely there has to be a reason/fix as to why the UPS believes it's not getting the 'correct' power from the generator?

Any boffins that can explain this to me?
Click to expand...
From my understanding.

A online UPS takes the incoming voltage (224V in your case) and downstep it to 12V or 24V, depending on the DC voltage of the inverter and then upscales back up to 230V 50hz pure sine wave therefore "cleaning" the power for you.

Pretty sure some other boffins here can explain it much better to you, but thats essentially what happens in a online UPS
 
TheMannequin said:
Thought the same... but they couldn't test it.

Will it be that it's too high or to low causing it?
Adding more load to bring it down if too high maybe?
Click to expand...
They can test it by investing in a decent multi-meter (FLUKE 77 series)
I am trying hard to remember I did have this issue once, there was an adjustment on the generator (I had to literally strip down the unit nearly entirely to find the control unit, and I was able to adjust it.. and that helped... but when loads came on and off the UPS would still click and beep but it would use the power provided...
 
ADrunkTeddyBear said:
From my understanding.

A online UPS takes the incoming voltage (224V in your case) and downstep it to 12V or 24V, depending on the DC voltage of the inverter and then upscales back up to 230V 50hz pure sine wave therefore "cleaning" the power for you.

Pretty sure some other boffins here can explain it much better to you, but thats essentially what happens in a online UPS
Click to expand...
The UPS I built does exactly that, so it cares not one iota for incoming power quality.
Some UPS units, fancier ones, measure frequency and so forth, to determine if power failure is imminent, and that's the deciding factor. You can probably change that setting. This one behind me has such a setting..
 
PaulMurkin said:
The UPS I built does exactly that, so it cares not one iota for incoming power quality.
Some UPS units, fancier ones, measure frequency and so forth, to determine if power failure is imminent, and that's the deciding factor. You can probably change that setting. This one behind me has such a setting..
Click to expand...
Some UPS's will pass through the current directly through them without any "cleaning", meaning that the power it receives is the power it passes on. And if it detects low/high voltage and frequency it will switch over to battery mode even though the power is technically still there

edit: attached link

community.fs.com

Line-interactive vs Online vs Offline UPS | FS Community

There are three topologies of UPS systems: offline vs line-interactive vs online. What are their differences and how to choose the right UPS system for your design? This article will make a comparison among these three designs in four aspects: operating principles; functions; benefits and...
community.fs.com community.fs.com

By the looks of it, it looks like OP has a offline UPS. Maybe OP can build a UPS like yours if its not too much of a problem, because DIY solutions are usually much cheaper than buying pre built.

He will also have the inverter module from his current inverter to play around with
 
It could also be that the voltage that the UPS is receiving is slightly too low. You can increase the voltage output by adjusting the AVR. It has a tiny screw on it that you turn clockwise to increase the voltage. Maybe push it up to about 230 volts? The AVR is normally located behind the end cover/cap on the alternator. On your model it should be on the generator frame on the right hand side of the battery behind a small metal cover. You will see some wires going into it from the alternator.
If the frequency is not correct please don't mess about with the generator speed, the frequency is controlled by the build of the alternator, the engine speed can only fine tune this. Take it back to the supplier to sort that out.
 
AlphaJohn said:
^ 100% this

Have that problem if I start generator with 0 load. So normally plug in a fan, then inverter goes back to AC.
Click to expand...
I solved this problem yesterday at friends of mine, their tattoo studio had the same issue... Cheap Mellerware Breeze room fan solved their problem
 
AlphaJohn said:
^ 100% this

Have that problem if I start generator with 0 load. So normally plug in a fan, then inverter goes back to AC.
Click to expand...
PaulMurkin said:
I solved this problem yesterday at friends of mine, their tattoo studio had the same issue... Cheap Mellerware Breeze room fan solved their problem
Click to expand...

......you must be ******* joking!
Loadshedding is at 16:00 today, so I shall give it a try and give feedback.

if not, I shall look into this:
Mike Angelo said:
It could also be that the voltage that the UPS is receiving is slightly too low. You can increase the voltage output by adjusting the AVR. It has a tiny screw on it that you turn clockwise to increase the voltage. Maybe push it up to about 230 volts? The AVR is normally located behind the end cover/cap on the alternator. On your model it should be on the generator frame on the right hand side of the battery behind a small metal cover. You will see some wires going into it from the alternator.
If the frequency is not correct please don't mess about with the generator speed, the frequency is controlled by the build of the alternator, the engine speed can only fine tune this. Take it back to the supplier to sort that out.
Click to expand...

Thanks!
 
TheMannequin said:
......you must be ******* joking!
Loadshedding is at 16:00 today, so I shall give it a try and give feedback.

if not, I shall look into this:


Thanks!
Click to expand...
I wasn't joking... I am an artist myself, we need power to ink people. Clean stable power is essential. Crappy power can lead to cutting a client's skin or ruining a beautiful piece of work...
 
Ok, so the fan didn't work....
I plugged it into the available 3 prong on the generator, and started it, same thing still. (I removed it after I checked the UPS's and they were still complaining.... should I have left it on?)

So, will now be looking at this, as the incomming Eskom power is sitting ~235v:
Mike Angelo said:
It could also be that the voltage that the UPS is receiving is slightly too low. You can increase the voltage output by adjusting the AVR. It has a tiny screw on it that you turn clockwise to increase the voltage. Maybe push it up to about 230 volts? The AVR is normally located behind the end cover/cap on the alternator. On your model it should be on the generator frame on the right hand side of the battery behind a small metal cover. You will see some wires going into it from the alternator.
Click to expand...
 
Mike Angelo said:
It could also be that the voltage that the UPS is receiving is slightly too low. You can increase the voltage output by adjusting the AVR. It has a tiny screw on it that you turn clockwise to increase the voltage. Maybe push it up to about 230 volts? The AVR is normally located behind the end cover/cap on the alternator. On your model it should be on the generator frame on the right hand side of the battery behind a small metal cover. You will see some wires going into it from the alternator.
If the frequency is not correct please don't mess about with the generator speed, the frequency is controlled by the build of the alternator, the engine speed can only fine tune this. Take it back to the supplier to sort that out.
Click to expand...
This did the trick! Thanks!
Pushed up the voltage to 235V, and all the UPS's are happy again!
 
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