Questions

Which UPS to buy?

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Which UPS to buy?

Johnny9183
I have a Dell XPS 8300 and 2 LED monitors. The power specs for the XPS8300 are as follows:

DC Power Supply

Wattage: 460 W
Input Voltage: 115/230 VAC
Input frequency: 50/60 Hz
Output current: 8A/4A

Now I am planning to buy a UPS for battery backup and surge protection. But despite hours of web research and chat with dell support, I am still not sure which UPS to buy. The Dell tech recommended this:

http://accessories.dell.com/sna/products/Power_Surge/productdetail.aspx?c=ca&l=en&s=dhs&cs=cadhs1&sku=A2388276&baynote_bnrank=0&baynote_irrank=0&~ck=baynoteSearch#Overview

But still I am curious to know what to look for while selecting a UPS. Is more wattage better? Won't it fry the system?

I am confused. Please help!

Thanks in advance.
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    OH Smeg

    Wattage is just a measure of available power. So if you have a choice between a 50 W and a 1200W the 1200W will run the system for much longer at the stated voltage.

    What you have to watch out for is Battery Life in any UPS so you want one with Good Batteries not cheap nasty batteries and ideally Jell Cell Batteries which will not leak in the event of the outer casing being broken.

    As for what you listed above it's OK and will give a reasonable amount of time on Battery but to be perfectly honest I'm not sure that it will be much of a Filter to absorb Power Surges and to be perfectly honest if you spoke to Dell you should expect them to recommend something that they sell. Doesn't mean it's better just that they will make money out of the sale.

    You should look at local Sellers in your area and see what if anything that they have available. Of course APC UPS's are the best available but they will cost you for the privilege.

    Col

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    Johnny9183

    Thanks Col. I was just wondering, is it ok to connect an UPS to a surge protector. So from the desktop's point of view, there will be 2 surge protectors, but I am not sure it will be safe.

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    chacok43

    Most UPS boxes you buy state that using a surge suppressor or even an extension cord between the wall and the power input to the box will void any warranty. It will actually slow down the switch-over to battery power in the event of an outage. In short, not a good idea.

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    Johnny9183

    Thanks for the tip. I would plug the UPS directly then.

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    0 Votes
    TheChas

    I personally recommend APC or Tripp-Lite over Cyber-Power for most users.

    APC has a number of guides and white papers to help you choose a UPS.

    I am running an older version of this UPS.

    http://www.apc.com/products/resource/include/techspec_index.cfm?base_sku=BE750G&total_watts=400

    This is the APC model similar to the Cyber-Power from Dell.

    http://www.apc.com/products/resource/include/techspec_index.cfm?base_sku=BR1000G&total_watts=200

    Keep in mind that for both the monitors and the computer you very seldom use the full power rating. I would expect your typical draw to be around 200 Watts.

    In addition to my computer and monitor, I run a cord from the UPS to my DSL modem and primary router.

    Chas

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    Johnny9183

    Great tip, didn't know that you don't use full rating always. Thank you!

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    1 Votes
    elibarikikilewo

    APC Smart-UPS 1000 has a new LCD alpha/numeric display providing detailed and accurate information previously restricted only to software or NMC. it also include flash upgradeable firmware and the most importantly it saves more time and it holds 3 year warrant

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    1 Votes
    trevorkrause

    There is a bit of confusion over what is a UPS (un-interrupible power supply) and what is a SPS (stand-by power supply).
    The SPS normally runs the load directly from the mains while charging or trickle-charging the battery. Only on a supply side fault or interruption, the unit in a finite time switches over to the battery until the mains supply is restored.
    The UPS maintains only the battery charge from the mains supply. The load takes it power directly from the battery via the inverter always. Therefore there is no changeover or switching of the power supply and any transients or brownouts on the supply side does not effect the load directly as they are separate systems connected only through the battery.
    The UPS is not as efficient in energy management as a SPS, but it is much better in maintaining a clean power supply to the load(computer etc).

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    0 Votes
    Johnny9183

    I didn't know anything about SPS. Thanks for introducing me!

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    0 Votes
    TheChas

    Interesting. By the definitions then, most of the home and small office UPS systems sold in the US are actually SPS systems. I have yet to use a portable "UPS" that runs off of the inverter when main AC power is present.

    I would expect that some large building and data center UPS systems are running off the inverter.

    Chas

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    JRez

    Make sure you buy an online UPS not offline. When power cuts and you have an offline UPS there is a small break in the power being sent to devices and servers do not like this. Online UPS the power is directed through the batteries. I recently took over a new position at a company and they had a cheap crappy UPS so I put in a EATON 9130, it cost around 5K but I know my servers (x4) are safe and if there is any power problems they will run for around an hour and half. Oh and some of the EATON UPS's have a network management card add-on, pretty cool.

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    mjd420nova

    Most all UPS units state their ratings as VAH (volt-amp-hours) This rating is mostly one for one to the wattage rating of the devices you connect to them. Example: A unit rated at 1,000 VAH will power a unit with a 1,000 watt rating for one hour. So for your case, with a 450 watt load, and a 1,000 VAH unit will run for about two hours. There are some very good units made by APC and Tripp-lite and are a bit expensive but are a commerical rating and used in small offices. All units need to be exercised on a monthly basis. The major failure will be in the batteries, most commonly the gel-cell type but easily replaced.

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    NickNielsen Moderator

    The units need to be exercised on a monthly basis and the major failure will be in the batteries.

    Most modern UPSs will automatically exercise themselves, particularly the enterprise-level units. They will also let you know when the batteries need replacing. A good battery (or set, in the larger units) should last three to five years. You can save money on the replacements by going to Batteries Plus or Interstate Battery. Both businesses will build the battery combination you need for your UPS at not much more than the cost of the batteries.

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    JPElectron

    Note that if you have a generator, or might in the future, don't get a cheap UPS. Because a generator won't output a steady 60GHz in the same way your electric company does, cheap UPS's are prone to cycling between battery and line (generator) which will wear out the relay and/or burn out the UPS.

    Unfortunately, the newer APC units with the LCD screen's all suffer from this problem, either because they were taken over by Schneider Electric who has an engineer with a screw loose, or simply cause they want you to buy the the more expensive "On-Line" series.

    For this reason and other's I've switched from liking APC to Tripp Lite and suggest the "double-conversion" or "online" type of UPS.

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    0 Votes
    NickNielsen Moderator

    The problem with generators is not the frequency, but the output voltage. Generators do not react well to changes in load at higher (>75%) load levels., and tend to voltage surges or drops. This is what causes your UPS to boost orattenuate the voltage, not the changes in frequency.

    If your generator doesn't maintain 60 Hz, it's time to look at the maintenance contract and find somebody who can set it up and maintain it properly.

  • +
    0 Votes
    OH Smeg

    Wattage is just a measure of available power. So if you have a choice between a 50 W and a 1200W the 1200W will run the system for much longer at the stated voltage.

    What you have to watch out for is Battery Life in any UPS so you want one with Good Batteries not cheap nasty batteries and ideally Jell Cell Batteries which will not leak in the event of the outer casing being broken.

    As for what you listed above it's OK and will give a reasonable amount of time on Battery but to be perfectly honest I'm not sure that it will be much of a Filter to absorb Power Surges and to be perfectly honest if you spoke to Dell you should expect them to recommend something that they sell. Doesn't mean it's better just that they will make money out of the sale.

    You should look at local Sellers in your area and see what if anything that they have available. Of course APC UPS's are the best available but they will cost you for the privilege.

    Col

    +
    0 Votes
    Johnny9183

    Thanks Col. I was just wondering, is it ok to connect an UPS to a surge protector. So from the desktop's point of view, there will be 2 surge protectors, but I am not sure it will be safe.

    +
    0 Votes
    chacok43

    Most UPS boxes you buy state that using a surge suppressor or even an extension cord between the wall and the power input to the box will void any warranty. It will actually slow down the switch-over to battery power in the event of an outage. In short, not a good idea.

    +
    0 Votes
    Johnny9183

    Thanks for the tip. I would plug the UPS directly then.

    +
    0 Votes
    TheChas

    I personally recommend APC or Tripp-Lite over Cyber-Power for most users.

    APC has a number of guides and white papers to help you choose a UPS.

    I am running an older version of this UPS.

    http://www.apc.com/products/resource/include/techspec_index.cfm?base_sku=BE750G&total_watts=400

    This is the APC model similar to the Cyber-Power from Dell.

    http://www.apc.com/products/resource/include/techspec_index.cfm?base_sku=BR1000G&total_watts=200

    Keep in mind that for both the monitors and the computer you very seldom use the full power rating. I would expect your typical draw to be around 200 Watts.

    In addition to my computer and monitor, I run a cord from the UPS to my DSL modem and primary router.

    Chas

    +
    0 Votes
    Johnny9183

    Great tip, didn't know that you don't use full rating always. Thank you!

    +
    1 Votes
    elibarikikilewo

    APC Smart-UPS 1000 has a new LCD alpha/numeric display providing detailed and accurate information previously restricted only to software or NMC. it also include flash upgradeable firmware and the most importantly it saves more time and it holds 3 year warrant

    +
    1 Votes
    trevorkrause

    There is a bit of confusion over what is a UPS (un-interrupible power supply) and what is a SPS (stand-by power supply).
    The SPS normally runs the load directly from the mains while charging or trickle-charging the battery. Only on a supply side fault or interruption, the unit in a finite time switches over to the battery until the mains supply is restored.
    The UPS maintains only the battery charge from the mains supply. The load takes it power directly from the battery via the inverter always. Therefore there is no changeover or switching of the power supply and any transients or brownouts on the supply side does not effect the load directly as they are separate systems connected only through the battery.
    The UPS is not as efficient in energy management as a SPS, but it is much better in maintaining a clean power supply to the load(computer etc).

    +
    0 Votes
    Johnny9183

    I didn't know anything about SPS. Thanks for introducing me!

    +
    0 Votes
    TheChas

    Interesting. By the definitions then, most of the home and small office UPS systems sold in the US are actually SPS systems. I have yet to use a portable "UPS" that runs off of the inverter when main AC power is present.

    I would expect that some large building and data center UPS systems are running off the inverter.

    Chas

    +
    0 Votes
    JRez

    Make sure you buy an online UPS not offline. When power cuts and you have an offline UPS there is a small break in the power being sent to devices and servers do not like this. Online UPS the power is directed through the batteries. I recently took over a new position at a company and they had a cheap crappy UPS so I put in a EATON 9130, it cost around 5K but I know my servers (x4) are safe and if there is any power problems they will run for around an hour and half. Oh and some of the EATON UPS's have a network management card add-on, pretty cool.

    +
    0 Votes
    mjd420nova

    Most all UPS units state their ratings as VAH (volt-amp-hours) This rating is mostly one for one to the wattage rating of the devices you connect to them. Example: A unit rated at 1,000 VAH will power a unit with a 1,000 watt rating for one hour. So for your case, with a 450 watt load, and a 1,000 VAH unit will run for about two hours. There are some very good units made by APC and Tripp-lite and are a bit expensive but are a commerical rating and used in small offices. All units need to be exercised on a monthly basis. The major failure will be in the batteries, most commonly the gel-cell type but easily replaced.

    +
    0 Votes
    NickNielsen Moderator

    The units need to be exercised on a monthly basis and the major failure will be in the batteries.

    Most modern UPSs will automatically exercise themselves, particularly the enterprise-level units. They will also let you know when the batteries need replacing. A good battery (or set, in the larger units) should last three to five years. You can save money on the replacements by going to Batteries Plus or Interstate Battery. Both businesses will build the battery combination you need for your UPS at not much more than the cost of the batteries.

    +
    0 Votes
    JPElectron

    Note that if you have a generator, or might in the future, don't get a cheap UPS. Because a generator won't output a steady 60GHz in the same way your electric company does, cheap UPS's are prone to cycling between battery and line (generator) which will wear out the relay and/or burn out the UPS.

    Unfortunately, the newer APC units with the LCD screen's all suffer from this problem, either because they were taken over by Schneider Electric who has an engineer with a screw loose, or simply cause they want you to buy the the more expensive "On-Line" series.

    For this reason and other's I've switched from liking APC to Tripp Lite and suggest the "double-conversion" or "online" type of UPS.

    +
    0 Votes
    NickNielsen Moderator

    The problem with generators is not the frequency, but the output voltage. Generators do not react well to changes in load at higher (>75%) load levels., and tend to voltage surges or drops. This is what causes your UPS to boost orattenuate the voltage, not the changes in frequency.

    If your generator doesn't maintain 60 Hz, it's time to look at the maintenance contract and find somebody who can set it up and maintain it properly.