The Power Is too much!!!

[alextreadwell]

I have been having power problems at the primary school I work for we get over voltages at least twice a day on the UPS I was just ignoring it, until I got called on on monday morning by a teacher saying that the servers had exploded ! when I got to the site the ups was off so I turned it back on and stared up the server. I checked with the teacher who had reported the servers exploding and they said that there was a flash, a very loud bang and everything stopped working. the school is just on the edge of the city and the the power has alway been bad is there andy one I can contact to try and get the power stabised or as all big companies do do they have a disclaimer that the quality fo the connection is "as is" and so long as your getting some then tough? I know most electrical products have tolerances to low and high voltages but to do this to the UPS then whats it doing to the other computers and switches I can't have a UPS for them all ?

[Geoff]

Contact the schools electricity supplier.

[birchanger]

It's not unusual for a UPS to report slight over-voltages. In fact if you Google you'll find posts about it, together with information on how to configure a SmartUPS to be a little more lenient.

 

Are you sure you haven't had a lightning strike nearby?

[richard2233]

Sounds to me like there is something spiking. What type of UPS is it? Majority of UPS's have the ability to handle electric spikes. If we have a standalone server that isnt attached to our network we tend to use APC-Smart UPS, they can withstand spikes up to 302v.

 

I would have thought its recieved a spike thats been too much and just switched itself off to protect the kit.

What type of UPS is it and what have you got running off it?

[Batman]

Isn't 230 volts supposed to be a rough target? I measured the voltage at my mother in law's house on Saturday, it's 240. Unless it goes above 250 I don't think it's a problem.

 

So... I'm not saying you're wrong but make sure it's not a problem with your UPS. We had a similar incident at the company I used to work for, and that was a faulty UPS. Never encountered it before or since, but I guess it's possible!!

[Andrew_C]

Isn't 230 volts supposed to be a rough target?

Sort of.

 

2.2.1 European Voltage Harmonisation

 

The nominal European voltage is now 230V 50 Hz (formerly 240V in UK, 220V in the rest of Europe) but this does not mean there has been a real change in the supply.

 

Instead, the new "harmonised voltage limits" in Europe are now:

230V -10% +6% (i.e. 207.0 V-243.8 V)

 

in most of Europe (the former 220V nominal countries), and

230V -6% +10% (i.e. 216.2 V - 253.0 V)

in UK (former 240V nominal)

 

This is really a fudge and means there is no real change of supply voltage, only a change in the "label", with no incentive for electricity supply companies to actually change the supply voltage.

 

To cope with both sets of limits an equipment will therefore need to cover 230V +/-10% i.e. 207-253V. This will actually become the official limit for the whole of the EU in 2003.

 

From here.

[richard2233]

:DYeah 230v is meant to be the correct voltage, on a house it is supplied at 240v. But on a school & businesses the incoming voltage tends to be alot higher because of possible systems it has to supply. We are just in the process of having ours upgraded.

 

But the point I was trying to make was if there is a problem incoming supply then there will be spikes thoughout the school. But depending on the UPS, some can handle higher electric spikes than others. Just something to think about thats all. Im more than likely well off the mark! Its the good thing about these Forums, always gives you something else to think about

[Andrew_C]

:DYeah 230v is meant to be the correct voltage, on a house it is supplied at 240v. But on a school & businesses the incoming voltage tends to be alot higher because of possible systems it has to supply. We are just in the process of having ours upgraded.

Sorry, just not true. Unless you are confusing 415V which is 3phase voltage. That is the voltage between phases, not phase to neutral. Or, you might be getting your own substation, but even then, the Low Voltage side (yes 240V is considered low voltage) must be 230 ±10%.

 

You might have a high voltage (but within the 10%) if you are close to the sub-station; conversely if you are at the end of a line you could be at the lower end of the range.

 

If your voltage is outside the range, get your supplier in to sort it out.

Edited July 2, 2009 by Andrew_C

[Batman]

Sort of.

 

This is what I thought

[synaesthesia]

One of my schools UPS's regularly reports it's receiving between 253 and 255volts up it's kettle-leaded jaxy. Absolutely no problem with it, other than lots of the usual overvoltage warnings. They had a pair of them (APC 700s) to start with which lasted just over 3 years before one died and the other started showing symptoms of following suit. Replaced with a single APC 1500 rackmount and it's quite happy at that voltage. I did double check with the site's supervisor and our own guys and apparently it's quite normal - then again if my memory serves me, the power's fed from a 3phase supply into the rackmount & busbars.

[Butuz]

I've got the opposite - during the day power sags to well under 220v some times as low as 210v. We also used to have quite alot of power cuts so I've overspecced the UPSs somewhat. We've got over 15 mins runtime on everything now.

 

The APC UPSs are doing a sterling job tbh!

 

Butuz

[SYNACK]

How to deal with this depends a lot on your power company. We had this problem a while ago with voltage reaching 260V at some points. We talked to the power company directly who plugged in a logging unit to the problem feed. They agreed that there was a problem but did not care enough to fix it.

 

When the new subdivision went in most of the problems went away. We also put in a dedicated feed for the server room which go tid of all of the rest of the issues.

 

This is one area where hp gear - UPSs - fall down quite spectacularly. Our hp ups at the time could not handle it properly at all and simply paniced and cut power, no shutdown attempt or event logged. In comparision the APC unit that we replaced it with filtered it out or gracefully shut it down. How bad the experience with bad power is usually comes down to how good your UPS is. HP appears to be rubbish in my experience, belkin is actually dangerous as a power cut to one of them blew a server PSU. APC is a big trusted brand, I'm sure there are others that are just as good but I have not encountered them yet.

[Andrew_C]

then again if my memory serves me, the power's fed from a 3phase supply into the rackmount & busbars.

Won't make any difference. You should lean on the supplier. They can change the output tap that feeds you in the sub-station to get you in spec. The damage to the UPS from significant long term overvoltage seems to be costing you money!

 

Butuz- They can up your voltage in the same way.

 

Ask them to stick a monitor on your supply; the circuitry in the UPS will not be calibrated so may be mis-reporting, so you really can only use it as an indication of a problem, rather than proof!