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how long UPS can support for a win2k server

how long UPS can support for a win2k server

how long UPS can support for a win2k server

Hi all,

I have a win2k server, running web, FTP and SMTP. It is connected to Internet by satellite, and connected to LAN by a switch. Several LAN PCs are connected to this server by that switch. I want a UPS for my win2k server. How long can a 3 kva pure sine wave line UPS can support the server during power shut off?

Some people say UPS normally only support 5-10 mintues. So short? Is there any one product can support 2 -3 hrs?

Thanks every expert
Replies continue below

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RE: how long UPS can support for a win2k server

What is the power consumption of your server? That will give you a ball park estimate of your current ups battery run time.
APC make a ups that you can add battery stack(s);but it is not cheap.

Rick Harris
SC Dept of Public Safety-DMV
Network Operations

RE: how long UPS can support for a win2k server

Sorry, I don't know exactly my server power consumpation.  I know, it is 1.6GHz Intel P4 CPU, 512MBRAM, two IDE 37GB hard disk, one 10M/100M Ethernet card, one 56k modem, the satellite modem, CD-ROM. It is configures as win2k server and provide some services. Can this give you some idea about its power consumption? What is the method to test it?

Don't have much knowledge of UPS before. Because find a big UPS promotion, so want to buy one, and hope the support time can reach 2hrs. One promotion produce is, the SMK-3000-LCD (3kva, pure sin wave, line interractiv UPS) before 3285$, now only 513$, so very attractive. But don't know if it is suitable for my requirenment or not.

RE: how long UPS can support for a win2k server

KVA is not a measurement of available run time it's a measure of load. 1 server will go no where near 3kva. The amount of run time that you'll get is dependant on how much reserve capacity (usually measured in Amp-hours(Ah) for a UPS) the battery or batteries have.

It's quite possible that you could go for 10 minutes to 100 hours on a 3kva depending on how many and how big the batteries are. The more batteries you have the more run time you'll get.

RE: how long UPS can support for a win2k server

Hi 12345671,

FredUG is totally right.  Most UPS are built with batteries allowing to last about 5 minutes at full charge, and you can *broadly* do the calculation: if half charge, you'll last 10 minutes.

If you want to last more longer, like two to three hours, I suggest you invest in a rectifier, batteries and a charge controller.  We use this here (in Kenya - bad power) for most ISPs, they can last 24 hours, with a full stack of batteries.  
The best way to enquire is to check with people providing solar power: they use the same kind of equipment and surely have what you need.
Investing in very big UPS will cost you a fortune.
Also, with the solar power-like systems, you can put as many batteries as you like and thus determine yourself the lasting time.
Mind that the major cost on long term is batteries.

The best method to test what your server consumes is to cut a power cable and put an ammeter in series with the machine.
I've looked at your config and I would say it consumes between 90W and 150W (without the screen).  Mind that most of the power consumption, apart from the CPU, is done by turning devices as floppy, CD, tape and HDD.  Your power consumption can raise a lot if you use tape, and floppy at the same time for example.  CPU power consumption and HDD is always the same (not when in sleep mode).

Hope it helps !


RE: how long UPS can support for a win2k server

Really thanks, very much.
Now, I know that for my server to run 2 hours, I need additional battery, and finally it could cost more than 2000A$, so at present, we may continue using our old USP which can support 20 mintues.

RE: how long UPS can support for a win2k server


Yes and no: it does not cost a lot if you're ready to do some "do-it-yourself".  Most UPS have user changeable batteries.  What you do: you pull out the wires, and connect them to another BIGGER battery.  Mind the voltage is has to be the same than the original battery.  Reach for a battery (deep cycle) that has "more" VA than the one in your UPS and your UPS will last longer (double the VA, you double the time), but won't be able to deliver more power than it is rated for (the system converting 12 VDC to 220 VAC remains the same with its limitations).
I've seen this at some people's and it looks a bit strange but it works perfectly.  And you don't need to bare the cost of a big UPS.

RE: how long UPS can support for a win2k server

To give you a ball park figure...
Have a SmartUps from APC, model 2200,(2000 watts)
Connected to a 2.8, single processor mobo
supermicro case has about 11 fans
7 raid drives
riple redundant Ps, at 600 watt
17 " monitor
intel 24 port switch
sonicwall firewall
cable modem

With everything connected, the APC software states I have 80 minutes run time.

RE: how long UPS can support for a win2k server

For a single server (including the video monitor), you should use a UPS with a minimum rating of 850 VA.  Be aware that no UPS produces its rated VA output, as power factor is often not considered.

Incidentally, buy a bigger unit just to increase the run time when on battery is wasteful.  The DC to AC conversion process isn't all that efficient, so battery capacity is expended just to generate AC.

BTW, I tend to steer my clients away from APC products, which  tend to be more hype than substance.  If you are really serious about high quality server power protection, take a look at the Powerware (formerly Best Technology) Ferrups line.

RE: how long UPS can support for a win2k server

I've ran 4 FreeBSD servers + 1 monitor off a single 500va UPS (not much run time though) so I have to disagree with 850va for 1 server unless it's a quad xeon or something with a high load. VA and watts aren't the same thing.

2 more cents,


RE: how long UPS can support for a win2k server

according to technome, the SmartUps from APC, model 2200,(2000 watts) should be able to support my server for at least 2 hours, but I seldom see the "watts parameter" on UPS product, they support only tell you the VA number.
How many batteries on this SmartUps from APC and how much is it?

RE: how long UPS can support for a win2k server

Yet to replace the batteries, but I believe they have 2 batteries. This unit has the batteries located in the lower part of the UPS, the electronics are on the upper section. Basically the batteries remain at room temperature; many other units are warmed by the electronics, which lowers battery life considerably.
Units are expensive new; also new UPS units can sit in storage for long periods of time. Have seen batteries dated 2 years to delivery date ( not good)
Purchased a few of these units in the last year from a company offering "refurbs". Search on the net for "refurbished APC". Some companies offer more than 1 year warranty on the batteries. Get insurance on the shipping.
As far as weight, they net weight 112 lbs. http://www.apc.com/resource/include/techspec_index.cfm?base_sku=SU2200J&language=en&LOCAL.APCCountryCode=ww

I have no problem saving 60% or more with a refurb; if it comes in with a couple of small scratches, and a warranty, big deal. Never get one on Ebay, they never pack the units properly, the United Parcel guys love to destroy heavy items.
To correct my self, the unit is 1600 watts. The load total wattage, unless you are connecting many servers is not as important as the battery amp/hours.
Basically I purchase larger units then needed. Considering the batteries capacity drops with age, I am sure they will last 3 or more years with the needed runtime; used smaller units but batteries need replacement more often.

RE: how long UPS can support for a win2k server

Hello every one, I am back again, I want to be 90% or higher sure the VA and Wattage of my PC running Windows 2000 server including the monitor. The configuration is same, but to save your time, I repeat and add more detail here:

1.6GHz Intel P4 CPU, 512MBRAM, two IDE 37GB hard disk, one 10M/100M Ethernet card, one 56k modem, 15" monitor, CD-ROM. It is running win2k server and provides FTP, web, SMTP and VNC services.

And there is a DirecPC satellite modem for internet connection. Any idea about the VA and wattage of the satellite modem?

Thanks very much, I am a bit impatient for the reply!!

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