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Need to understand UPS equipment better

700 VA  - 240 Watts
Up to 75 minutes
6 outlets
IMG_0402.jpg

What's VA?  What's master and controlled master do for the outlets on a UPS. Also, how do I spec out usable (battery backup) outlets?  Does the USB safely power down the server?  Does the safe shutdown feature work for NAS equipment too or other IT items?  Is their third party software?  I was specing out the UPS below too...  how do I spec out usable (battery backup) outlets?

CyberPower PFC Sinewave Series OR1000PFCRT2U
UPS (rack-mountable / external) - AC 120 V - 700 Watt - 1000 VA 9 Ah - USB, serial -
output connectors: 8 - 2U
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snoopaloop
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snoopaloop
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6 Solutions
 
nobusCommented:
VA is voltage x Ampères = POWER in Watts; to discern it from the AC  power (cosinus factor)
but why not contact Cyberpower with the questions?  they should be able to help you out? no?
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snoopaloopAuthor Commented:
Because I don’t have the time or the resources to contact them so I have EE subscription instead.
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Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
700 VA is approximate to 700 watts of equipment

But If you attach 700 watts of equipment you can expect a very short run time on battery

Most OS and NAS now support UPS direct no additional software is required

This master option looks priority to Cyberpower

It obviously has some sort of control if power goes off controls the second power outlet
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snoopaloopAuthor Commented:
Ok, great.  So they automatically know to shut down the system when the power is getting weak.  

The master option looks priority to cyberpower?  Can you elaborate?  I'm not following that statement.

Has some control?  Can you elaborate ?
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Mal OsborneAlpha GeekCommented:
In the contemporary IT world, VA is an irrelevant bullshit term used to make UPS seem more powerful than they really are. Just pay attention to the rating in Watts. Watts is volts multiplied by amps, assuming both are in phase, and have the same waveform. For a resistive load, like a small heater this is true.  In eras past, it was common for loads to be inductive; this meant that voltage and current were out of phase. Motors and transformers are inductive loads.  Phase angles made sense with capacitive or inductive loads.  With an inductive load, 500watts may be 505VA, or 1000VA, or 10000VA.  With contemporary IT equipment however, the usual load will be an SMPS. (Switch Mode Power Supply)  With these non-linear devices, phase angles make little sense; voltage will be a sine wave, but current will be a series of short pulses aligned with the peak voltage.  

Also, it is often not easy to figure out real power consumption for devices. A PC, for example may have a 600W power supply, but only draw 120W. Realistically, you need to grab a stopwatch, then "suck it and see" to determine runtime. Usually, it is best to overspec a little.

Also, most UPS manufacturers lie. Usually run times will be significantly shorter than the published specifications suggest. If you set up a test rig with some lightbulbs as a linearish load, and a couple of DVMs you might manage to get 80% of the published runtime.

The "Master" and "Controlled" outlets are not usual on a UPS; some UPS and power boards have them. Basically, when current is drawn form the "Master" outlet, the "Controlled" ones power up. You may, for instance plug your PC into the "Master" outlet, and your monitor and printer into the "Controlled" outlets. That way, when you turn the PC on the peripherals power up, when you shut it down they turn off. Saves having manually flick a few more switches.  

Usually a UPS will come with some sort of proprietary software for a range of operating systems. Older devices typically  used  RS-232, but newer UPS normally have a USB connection. The software typically shuts down the machine it is connected too, and will allow a script to be fired to shutdown the rest.
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andyalderCommented:
The Master and controlled by master is to shut down peripherals as well as the PC/server.
http://manualzz.com/doc/6594401/user-manual-and-warranty
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snoopaloopAuthor Commented:
Thanks guys for the really in depth material.   @ Andy I saw your document.   I'm curious, can I get power adapters that make sure they don't draw power when "off" regardless of computer being in play in the scenario.  Is the Cyber Power or an industry wide standard power strips sometime follow with "master" and "controlled Master"

@Mal I really appreciate the break down.  I guess my questions play into the question above about what I should be look for when specn out a UPS and trying to figure out the outlet situation.  It looks my illustration only allow for three battery backed up outlets.   Are these industry wide lingo  "master" and "controlled master?"
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Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
Calculate total wattage of all equipment you want to
Protect?

If you need LCD screens we don't usually bother connecting LCD screens only servers

Then work out what runtime you require to keep the equipment running before shutdown

E.g 15 minutes

This will give you your Size if UPS

Larger UPS larger number of outlets

We use Eaton
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nobusCommented:
what do you mean with " can I get power adapters that make sure they don't draw power when "off" regardless of computer being in play in the scenario. "  what do you want to achieve?
as said, if you want to know the power needed - do a rough calculation
add power needed per PC + external devices, like NAS to get a total; say 800 W
add 10% margin - that's your power
choose the time it needs to run without power - -30 min?
then the needed KWH = total power = KVA x Hours = 800x 1/2 = 400 W Unit needed
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andyalderCommented:
The UPS cuts the power to the "controlled by master" sockets when it powers the main PC/server outlet socket off, probably with a relay. Anything plugged into that can not draw any power when off. Those sockets are not protected by the UPS though so they will still go off and on again if there is a short power-out whereas whatever is plugged into "Master" will stay powered on.
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Mal OsborneAlpha GeekCommented:
The "Master" and "Controlled" outlets are not common on UPS; this is an unusual device in that regard. Thus there in no standard lingo.   It is not a feature that would be all that useful for servers, but could be used on a PC or home stereo system.

Although there are limited outlets, it is possible to use power boards to fan this out to may devices.
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