Power Cuts
#21
Posted 25 January 2010 - 07:04 PM
Decided against the UPS idea when I realised i'm running:
3x Fluval 404
1x Eheim 2215
2x Eheim Pro3 2075
They add up real quick, next time i'll have to say no to myself when I see a new canister filter at my LFS.
Hope my plan holds up.
#22
Posted 26 January 2010 - 09:44 PM
#23
Posted 26 January 2010 - 10:30 PM
#24
Posted 26 January 2010 - 10:50 PM
#25
Posted 27 January 2010 - 07:40 AM
#26
Posted 27 January 2010 - 07:47 AM
#27
Posted 27 January 2010 - 09:43 PM
obviously this depends on the make/model, but the eheim classic would have no worries with this...
#28
Posted 27 January 2010 - 10:38 PM
I think that is incorrect Kev
VA rating is the same as watts which is power flow per hour.
So to work out how long it will last for you add up all the wattages for all your equipment and divide the UPS rating by that no
In your example it is 700va / 25
So it would run for about 28 hours (In a perfect world with no loss.....)
Thats what I was taught anyway....
Cheers
Andrew
#29
Posted 27 January 2010 - 10:44 PM
EDIT: Also I assume a UPS has some sort of moified sine wave inverter built in, which I really can't see being more than about 85% efficient, which would have to be factored in too.
#30
Posted 28 January 2010 - 07:23 AM
VA rating is the same as watts which is power flow per hour.
So to work out how long it will last for you add up all the wattages for all your equipment and divide the UPS rating by that no
In your example it is 700va / 25
So it would run for about 28 hours (In a perfect world with no loss.....)
Thats what I was taught anyway....
Cheers
Andrew
I think you're right, Andrew..
Maths isn't my strong-point (hated it in school).
#31
Posted 28 January 2010 - 09:14 AM
To quote Brian from half-baked "It's more complex than that!"
The wattage isn't flow of power per hour. It's the amount of energy the appliance consumes.
I don't have time to go into now, but have a look at the wikipedia page for Wattage and for Volt-amps...they are (suprisingly!) good for a brief explanation.
They give the specs in VA because it doesn't directly translate to Watts (due to power factor) but it looks a lot higher
Bit like amplifiers and other electrical appliances which give the power ratting in peak-peak wattage, which looks really nice on the box, but is actually pretty meaningless in reality
cheers
ado
#32
Posted 28 January 2010 - 09:28 AM
700va UPS will run a 25W AC load for around 2 hours.
#33
Posted 28 January 2010 - 10:47 PM
My bad!
On a side note ratings such as 700va and 2000w pmpo really annoy me!
Why cant ups's say the 1hr power rating like batteries. Grrr
And stereo systems just say rms?
Stupid imaginary useless confusing ratings.
#34
Posted 29 January 2010 - 08:31 AM
yeah kev thats the one
#35
Posted 29 January 2010 - 08:33 AM
There is an old saying that some is up pretty well...Merda taurorum animas conturbit
Mass produced stereos and amplifiers are some of the worst. Giving ratings in peak power so that together with the flashing leds and fancy design speaker fronts some poor unsuspecting consumer is conned into thinking he is getting something spectacular and happy to pay top dollar.
#36
Posted 30 January 2010 - 09:13 PM
Ryan
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