UPS

[Godzilla]

I bought a 1300VA UPS (Trust 15601) and its rated to last "up to 70 minutes". On my system (see sig) it barely lasts 5 minutes before it shuts down the PC for me. At first I thought this doesn't seem right, so I took it down to the computer shop from where i bought it and told them to test it on their machine. It lasted well over 45 minutes and it was still going, so that made me look a bit stupid. So it obviously wasn't a faulty UPS.

My question is, is my system really pulling so much power that a UPS charge only lasts less than 5 minutes? Baring in mind this is at idle (37% load according to the management software) and no overclock etc.

Also what is 1300VA in terms of Watts?

 

[shant]

1300VA is not 1300W its much more less, i don't know how to calculate them but
i have a 850va ups wich puts out 480W (according to manufacturer)
so id say around 650-700W output (sorry im bad at math)
sounds to me you don't have enough power, try a lower end pc with the same power cables and see how it holds up

 

[noxqzs]

Power factor determines the ratio of VA to Watts for AC circuits, and it can be in a range of .6 to 1 being equal. For example a 1000VA could either be rated for 600Watts or 1000Watts. It is important to note that this does not give you an indication of how long the system will last. The value you need for that is Watt-hour or Amp-hour. For your system, I highly doubt you would come close to a 70 minute backup time, and I actually believe the 5 min.

To give you an example, if your PC was drawing 1000W from the UPS @ 120V, then you would be consuming 8.3Amps of current. To run that pc off of the battery backup you would need a total of 8AmpHours of AC power. In addition to the losses of converting the batteries DC power to AC, the amount of charge it would need to store would be huge.

 

[David]

The figure of 70 mins (and the 45 min test) is most likely for a standard desktop machine (think low-mid spec. Dell) at idle. Is your system under load? We have a UPS on a mission-critical machine in the office and the difference between battery life under load and at idle is noticable.

 

[Godzilla]

The figure of 70 mins (and the 45 min test) is most likely for a standard desktop machine (think low-mid spec. Dell) at idle. Is your system under load? We have a UPS on a mission-critical machine in the office and the difference between battery life under load and at idle is noticable.

idle.

 

[Godzilla]

anymore input from anybody?

Noone still not said how much 1300VA is in terms of Watts?

 

[Automata]

Unless I understand this wrong, VA is volt-ampere. Basically, Volts * Amps. Since you know the voltage is around/at 120, the available amperage is ~10.833; which is 1300 watts.

I believe that doesn't mean the device can do 1300 watts, as that would be limited by the internals of the UPS, but it should be around that. Why are you not checking the device's specifications? They should be clearly printed on their website or the device itself.

 

[Godzilla]

Unless I understand this wrong, VA is volt-ampere. Basically, Volts * Amps. Since you know the voltage is around/at 120, the available amperage is ~10.833; which is 1300 watts.

I believe that doesn't mean the device can do 1300 watts, as that would be limited by the internals of the UPS, but it should be around that. Why are you not checking the device's specifications? They should be clearly printed on their website or the device itself.

This is my UPS: http://www.trust.com/products/product.aspx?artnr=15601

Wattage is not stated. Btw how do we know the voltage is around 120? In England the voltage from our sockets is 230-240v if thats what you mean

 

[Automata]

Either way, it would still come out to the same wattage.

1300 / 230 = ~5.65
~5.65 * 230 = 1300

Wattage = Volts * Amps
Since VA is Volts * Amps, it should be the same.

I just pulled the manual for this unit and it doesn't specify. I've never heard of this company, but I've never really looked around. It will probably do what you want, but do you have to have this exact one?

 

[Godzilla]

Either way, it would still come out to the same wattage.

1300 / 230 = ~5.65
~5.65 * 230 = 1300

Wattage = Volts * Amps
Since VA is Volts * Amps, it should be the same.

I just pulled the manual for this unit and it doesn't specify. I've never heard of this company, but I've never really looked around. It will probably do what you want, but do you have to have this exact one?

was the best (highest minutes) one my local comp shop had. They have a newer model of it but that is only 45 minutes yet same VA? Here: http://www.trust.com/products/product.aspx?artnr=17238

Can you explain why they are both 1300VA but 25 minutes difference? lol

 

[Automata]

VA is throughput, like amperage. You don't rate battery longevity purely on amperage. Meaning, you could have a small battery, but it puts out a ton of current (high VA). You could also have a very large battery that puts out moderate current, but goes for much longer.

For simplicity, treat VA like watts; it makes it easier to understand. The higher the VA, the higher load it will support. Battery life will be determined (mainly) by the battery size and how much load is on it.

 

[shant]

that actually makes sense, pretty sure not enough power for your pc

edit:just thought of this, you probably have the data cable connected to your pc, check your pc power settings, makes sure you don't have it set to turn off when on battery or something like that (if there is an option like that lol) i know it sounds stupid but there's a first time for everything

 

[Automata]

Here is another explanation and I hope it clears up.

My computer will run on my UPS for roughly 5-7 minutes before it shuts down. On this same UPS, I could run my LED lamp for weeks or maybe even months. The battery only has so much energy to give. So, if you take it faster, it doesn't last as long.

The same exact scenario applies to your first post. Their "70 minutes run time" is probably a bit optimistic to begin with, in combination with a very low end desktop with almost no peripherals running (monitors, etc). Even an idle low end gaming system is going to half that without a problem. Start tacking on what you got, and 5 minutes sounds just about right.

----

Another comparison I thought of, and I'm sure this isn't 100% accurate, but I think it explains it well. You have two vehicles, one a "normal" vehicle and the other a sports car. With your system, you are effectively driving this sports car at full tilt and wondering why you are running out of gas 75 miles down the road when the "normal" vehicle is going much further. It is all about how you use your "gas" (battery).

 

[Godzilla]

that actually makes sense, pretty sure not enough power for your pc

edit:just thought of this, you probably have the data cable connected to your pc, check your pc power settings, makes sure you don't have it set to turn off when on battery or something like that (if there is an option like that lol) i know it sounds stupid but there's a first time for everything

No such option for battery on a PC. But I have all other power saving options turned off anyway.

Here is another explanation and I hope it clears up.

My computer will run on my UPS for roughly 5-7 minutes before it shuts down. On this same UPS, I could run my LED lamp for weeks or maybe even months. The battery only has so much energy to give. So, if you take it faster, it doesn't last as long.

The same exact scenario applies to your first post. Their "70 minutes run time" is probably a bit optimistic to begin with, in combination with a very low end desktop with almost no peripherals running (monitors, etc). Even an idle low end gaming system is going to half that without a problem. Start tacking on what you got, and 5 minutes sounds just about right.

----

Another comparison I thought of, and I'm sure this isn't 100% accurate, but I think it explains it well. You have two vehicles, one a "normal" vehicle and the other a sports car. With your system, you are effectively driving this sports car at full tilt and wondering why you are running out of gas 75 miles down the road when the "normal" vehicle is going much further. It is all about how you use your "gas" (battery).

Good example. I just bought 1 of those power meter things and it says i'm drawing 320W at idle. Does that sound right?

 

[shant]

320w sounds right to me with that 295

 

[Badbonji]

At idle? I think that is a little high. I was expecting around 150-200W considering the CPU is also stock...

 

[Godzilla]

At idle? I think that is a little high. I was expecting around 150-200W considering the CPU is also stock...

yep idle. My other 2 systems were pulling 140W and 240W, but they are not as beasty as this machine

 

[shant]

i say its normal with a 295, the 295 is as power efficient as current video cards

 

[noxqzs]

was the best (highest minutes) one my local comp shop had. They have a newer model of it but that is only 45 minutes yet same VA? Here: http://www.trust.com/products/product.aspx?artnr=17238

Can you explain why they are both 1300VA but 25 minutes difference? lol

1300VA is the equivalent of saying 1300VoltAmps which is the same as saying 1300Watts. There is one caveat to this, and that is the battery inside the units have DC voltage. You cannot convert from DC to AC and have a 1:1 power factor. There are losses in the system and usually you end up with anywhere from .6 to .9 of actual value. In your case, that determines the maximum power that you can draw from any of the plugs combined.

Best case scenario, plus or minus depending on how good your psu is, would be:
1300 x .9 (PowerFactor) = 1170Watts.

With 230Volts power source, that would mean the maximum current that you could put out of the PSU before overloading it is:
1170W /230V = 5.08Amps

Since you know that your pc is consuming 320W at idle, your current consumption at idle is:
320W/230V = 1.39Amps

If your psu lasts 5 minutes, then the time it lasts is:
5min x 1hr/60min = .083hrs

Since we are considering the total power consumption of the psu and pc, we need to use the total wattage, including losses during conversion. Based on 1300W and 230V, according to Thideras, total current consumption is 5.68Amps.
This would equate to a battery that has a capacity of:
5.68A x .083hrs = .47AmpHour


So in summary. The VA number is not representative of the total power you can use, it just tells you how much total power at any given voltage you will draw from the wall socket. The capacity of the battery is what determines how long the system will last. Doubling a psus capacity would be equivalent to doubling the amount of fuel two identical cars can store. In your case, it could be an extra battery in the psu running in parallel.