Any Recomendations for a UPS Power Supply?

[Davisonp]

Hi,
Can anyone recommend a low cost UPS to clean up a power supply?
Also, I was wondering if a UPS would synchronise the output sine wave phase to the input phase?

 

[Pete999]

Hi,
Can anyone recommend a low cost UPS to clean up a power supply?
Also, I was wondering if a UPS would synchronise the output sine wave phase to the input phase?

If you are looking for a clean supply rather than a back up supply, why not go for a Motor/Alternator set up or a Voltage Stabiliser

 

[HandySparks]

A power rating and a bit of background info would help.

 

[Davisonp]

I have been asked to investigate a problem with 12V thin client computers not booting (blue light comes on when button pressed, but the computer then shuts down).
The IT team are convinced there is a “Fault” in the supply somewhere.
Investigating the issue, if the computer is moved from the office to another part of the building and plugged in, the computer boots successfully.
The existing transformer is outputting 12.6Volts.
There is no problem on the ring so it appears there is an issue with the supply, which could be a nightmare and very expensive to find and fix.

The existing supply has an output max of 36 Watts (3 Amps at 12Volts). There are 5 computers in one room, and 4 in another but there could be multiple UPS’s if required.

The UPS is only being used to clean the supply, nothing else.

I have recommended trying with a regulated 12Volt power supply instead of the supplied unregulated supply and see if the superior supply handles the supply problems.

I believe a guaranteed solution would be to get a “Continuous” UPS to run the computers, that way you are running the computers through an inverter from the battery giving a clean sine wave with a good voltage.

I hope this makes sense.

 

[HandySparks]

Fitting a UPS feels to me like the wrong fix.

I'd check R1, R2 and Rn for the circuit and measure Zs and the supply impedance (like Zs, but L to N). Also check whether there's some other noisy load on the circuit which might affect the computers. After that I'd get a like for like replacement for the PSUs in case there's a faulty batch. If the PSUs and computers can't work with a normal UK supply, there's something wrong with them.

 

[Strima]

What's the earthing arrangement on the circuit? Is it a high integrity circuit?

 

[Davisonp]

Fitting a UPS feels to me like the wrong fix.

I'd check R1, R2 and Rn for the circuit and measure Zs and the supply impedance (like Zs, but L to N). Also check whether there's some other noisy load on the circuit which might affect the computers. After that I'd get a like for like replacement for the PSUs in case there's a faulty batch. If the PSUs and computers can't work with a normal UK supply, there's something wrong with them.

Fitting a UPS feels to me like the wrong fix.

Yes, but I cannot think of an alternative.

I'd check R1, R2 and Rn for the circuit and measure Zs and the supply impedance (like Zs, but L to N).

Zs about 0.43Ω Live to neutral loop 0.35

Also check whether there's some other noisy load on the circuit which might affect the computers.

I don’t know where to start with that.

After that I'd get a like for like replacement for the PSUs in case there's a faulty batch.

Tried that today. Replaced unregulated transformer with completely different brand of transformer with regulated output and got exactly the same results. Also, these transformers work in other parts of the building.

If the PSUs and computers can't work with a normal UK supply, there's something wrong with them.

I agree, however, when a high quality independent regulated output transformer makes no difference, it implies something happening in the mains coming into the room.

 

[Davisonp]

What's the earthing arrangement on the circuit? Is it a high integrity circuit?

The building is TNC-S and yesterday I converted one ring to a high integrity earth setup including splitting the earth at the distribution board with no improvement.

I do struggle to understand how the earthing system could affect unearthed equipment?

 

[Strima]

The building is TNC-S and yesterday I converted one ring to a high integrity earth setup including splitting the earth at the distribution board with no improvement.

I do struggle to understand how the earthing system could affect unearthed equipment?

Switched mode power supplies and the like require a good earth as the rectifier capacitors like to dump to earth. A poor earth and the PSU won't run properly.

Just out of curiosity is the CPC the same CSA as the conductors?

Have you tried just running one PSU on the circuit? Is there anything else connected such as printer, photocopier etc?

 

[Davisonp]

Switched mode power supplies and the like require a good earth as the rectifier capacitors like to dump to earth. A poor earth and the PSU won't run properly.

Just out of curiosity is the CPC the same CSA as the conductors?

Have you tried just running one PSU on the circuit? Is there anything else connected such as printer, photocopier etc?

There are three separate rings in three offices all next to each other. The earth is 1.5mm.
I converted one ring with 8 sockets into a high integrity earthed ring.
On this ring, there are only three sockets in use. One with an extension lead with 6 things plugged in. There are 4 computers and 4 screens, and one Samsung phone charger.
Since the problem occurs in all three offices, it appears to be either a problem from outside, or that the computers are particularly vulnerable to interference (which is what I suspect) as no other computers in the building have this issue, only the new ones in the three offices, not the old ones that have been replaced.

 

[Strima]

Very strange, I'm a bit stumped at the minute.

 

[Davisonp]

Very strange, I'm a bit stumped at the minute.

Yes, I am stumped too.

I forgot to mention that the computers were replaced a short while ago, and the new computers had this issue immediately and ever since, but the old computers of various manufactures never had an issue.

I think there is a slight dirty electricity issue in the building, but that the new computers are over sensitive to this but the bosses want the issue solved and the computer company are blaming the supply.

 

[Strima]

The computer company would blame the supply. What make of PSU are they?

 

[DPG]

Wouldn't cost much to get a small UPS to try with one of the computers - would give you more to go on then.

 

[Pete999]

Judging from your responses, you haven't even entertained my suggestions, just plumped for the UPs syndrome, which isn't going to provide you with what you want
My suggestion would be rather than hoping to find the answer to your problem, from well meaning and informed replies, you may do better by laying out the exact problem and what you have/are doing about it and go to a reputable power supply company, explaining your concerns, asking for a site visit, so they can see first hand the environment and working conditions, you may be pleasantly surprised by the responses.
Dduring my time as Head of of the electrical section where I worked I found most firms would visit FOC to offer their equipment as a remedy for your problems, could save you or your company a lot of unnecessary time and money.

 

[Davisonp]

Wouldn't cost much to get a small UPS to try with one of the computers - would give you more to go on then.

This is what I have suggested. A “Continuous” UPS for less than £200.

I was wondering whether the UPS will synchronise with the supply phase (like the PV inverters)?

 

[Davisonp]

The computer company would blame the supply. What make of PSU are they?

Elementech, however I am suspicious that it may be fake. According to the information on the back, the output is 36 Watts, however, the input is somewhere between 200 Watts and 480 Watts so very inefficient if correct.

 

[DPG]

No, but it shouldn't need to syncronise to incoming phase.

 

[Davisonp]

Judging from your responses, you haven't even entertained my suggestions, just plumped for the UPs syndrome, which isn't going to provide you with what you want
My suggestion would be rather than hoping to find the answer to your problem, from well meaning and informed replies, you may do better by laying out the exact problem and what you have/are doing about it and go to a reputable power supply company, explaining your concerns, asking for a site visit, so they can see first hand the environment and working conditions, you may be pleasantly surprised by the responses.
Dduring my time as Head of of the electrical section where I worked I found most firms would visit FOC to offer their equipment as a remedy for your problems, could save you or your company a lot of unnecessary time and money.

Sorry Pete, I had intended to answer but got distracted.

Yes, a clean supply would be ideal. I have no experience of the Motor/Alternator set up or voltage stabiliser. Is there somewhere I can read up on them?

With this post, I agree entirely about getting the experts in, however, I suggested to the bosses that to confirm a problem with dirty power supply in the building they needed to approach a specialist or advice and diagnosis, even giving them a linl to a company that I had found that do specialise in this sort of thing, and I think they expect this to be expensive so have not even explored it but are still wanting a reliable solution to their problem.

When you say “go to a reputable power company” do you mean the supply company, or is there someone you would suggest they approach?

Personally I am not convinced there is a real problem in the building (block of flats with 9 floors and offices on the ground floor, and the offices are where the problem is occurring). There has not been an issue with any IT equipment before these new computers (IGel Computers) arrived, and the problem was then instantaneous and consistant.

 

[Pete999]

Sorry Pete, I had intended to answer but got distracted.

Yes, a clean supply would be ideal. I have no experience of the Motor/Alternator set up or voltage stabiliser. Is there somewhere I can read up on them?

With this post, I agree entirely about getting the experts in, however, I suggested to the bosses that to confirm a problem with dirty power supply in the building they needed to approach a specialist or advice and diagnosis, even giving them a linl to a company that I had found that do specialise in this sort of thing, and I think they expect this to be expensive so have not even explored it but are still wanting a reliable solution to their problem.

When you say “go to a reputable power company” do you mean the supply company, or is there someone you would suggest they approach?

Personally I am not convinced there is a real problem in the building (block of flats with 9 floors and offices on the ground floor, and the offices are where the problem is occurring). There has not been an issue with any IT equipment before these new computers (IGel Computers) arrived, and the problem was then instantaneous and consistant.

Davisonp, post: 1294630, member: 29842"]This is what I have suggested. A “Continuous” UPS for less than £200.

I was wondering whether the UPS will synchronise with the supply phase (like the PV inverters)?[/QUOTE]

Sorry Pete, I had intended to answer but got distracted.

Yes, a clean supply would be ideal. I have no experience of the Motor/Alternator set up or voltage stabiliser. Is there somewhere I can read up on them?

With this post, I agree entirely about getting the experts in, however, I suggested to the bosses that to confirm a problem with dirty power supply in the building they needed to approach a specialist or advice and diagnosis, even giving them a linl to a company that I had found that do specialise in this sort of thing, and I think they expect this to be expensive so have not even explored it but are still wanting a reliable solution to their problem.

When you say “go to a reputable power company” do you mean the supply company, or is there someone you would suggest they approach?

Personally I am not convinced there is a real problem in the building (block of flats with 9 floors and offices on the ground floor, and the offices are where the problem is occurring). There has not been an issue with any IT equipment before these new computers (IGel Computers) arrived, and the problem was then instantaneous and consistant.

Try this lot they may be able to help, it's been a while since I used anyone,Voltage Stabilizers - Single and Three Phase Stabilizer Solutions - https://www.ashleyedison.com/voltage-stabilisers-660/?gclid=EAIaIQobChMIrf3y6Kbh1QIVVMYbCh3kewOMEAAYASAAEgLpZ_D_BwE