There’s nothing worst when working on a document, performing research, or breaking down the numbers in your books and the power goes out.  The computer goes out, the server reboots, and the internet is nowhere to be found.  We all have been there at some point but it doesn’t have to be this way.  Protecting your data and your IT infrastructure from power outages should be on the top of the to-do list.  The most critical pieces to protect are your desktop computers (if you habit of storing data locally on your computer) and your servers.  Your modem, routers, and switches tend to get neglected but it’s definitely worth considering if you can budget for it.

UPS Battery Backup Support is one topic that requires your full undivided attention as a individual supporting IT hardware infrastructure.  You should be a UPS battery and power consumption expert if you spend an hour here.  Enjoy!

How do I budget for the right UPS or UPS’s?

An average desktop computer has a power usage of between 80 and 250 watts hour of “active” use, depending on graphics cards and additional peripherals.    A laptop is 50 to 100 W/hour.  In stand-by mode the power consumption of both a desktop and a laptop falls to about a third.   The cost to the University to operate a typical computer and monitor workstation (130 watts @ 11c kW/h) for 24 hours per day, 7 days per week, 365 days per year, is $129.73.

For instance, one server can use between 500 to 1,200 watts per hour, according to Ehow.com. If the average use is 850 watts per hour, multiplied by 24 that equals 20,400 watts daily, or 20.4 kilowatts (kWh).

The Math Breakdown:  850/1000 = .85  x 24 = 20.4 kWh

Multiply that by 365 days a year for 7,446 kWh per year.

Another Network Device Power Consumption Example:

Synology NAS Power Consumption*

17.23 W (Access)
5.4 W (HDD Hibernation)

Not Clear Yet?

The power company bills you on Watts consumed (Kilowatt Hours). A Kilowatt Hour is 1000 watts per hour.  Here’s an example of of active usage for the current billing cycle of like 22 days.  This works out to be 207.31 kWh or like 9 kWh each day.  My laptop alone could potentially produce  if used for like 10 hours of that day produce 1 kWh of that 9 kWh.

Watts (100 watt laptop) in use X cost/KWH X hours per day X days per week X 52 weeks / 1000

Still Not Clear?

1 kWh is 1000 Watts consumed for an hour. My laptop consumes 100 watts of that 1000. We will explain more below.

How to convert watts to kilowatts

ProTip! None of this makes sense unless you first convert your electronics Watts usage an hour to killowatts.

1kW = 1000W

Watts to kilowatts conversion formula

The power in kilowatts P(kW) is equal to the power in watts P(W) divided by 1000:

P(kW) = P(W) / 1000

Example

Convert 1300W to kilowatts:

P(kW) = 1300W / 1000 = 1.3kW

The Laptop Example:

Or in my laptop example that uses or consumes a 100 watts per hour…

Convert a 100 Watts to kilowatts

100 W/1000 kW = .1 kw hour

We will continue more laptop power consumption scenarios down below.

Watt to kilowatts conversion table

Power (watts) Power (kilowatts)
0 W 0 kW
1 W 0.001 kW
10 W 0.01 kW
100 W 0.1 kW
1000 W 1 kW
10000 W 10 kW
100000 W 100 kW
1000000 W 1000 kW

100 Watts Laptop Consumption an Hour (Continued)

We should all know now we are dealing with .1 kw hour laptop usage. Let’s add additional (watts X time) time usage of the laptop.

that is 0.1 kw hour

Add more time…
0.1 kw hour for 10 hours (.1 x 10) = 1 kw hour

The 1 kWh of laptop consumption brings us full circle to the graph up top.

More Energy Consumption

Fun Fact! According to the US Energy Information Administration (PDF), the average kWh cost for commercial use from January 2012 through January 2013 was 9.83 cents. So that means it would cost $731.94 to power the aforementioned server for one year.

Am I being eco friendly?

Here’s a fun and easy to use calculator to find out.

I want UPS backup now that I understand Watts. Here are the UPS Specs…

700 VA – 240 Watts
Up to 75 minutes
6 outlets

  • What’s VA?
    • In the contemporary IT world, VA is an irrelevant BS term used to make a UPS seem more powerful than they really are. Just pay attention to the rating in Watts.
  • What’s my PC’s real power consumption?
    • The PC may have a 600W power supply, but only draw 120W. 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 run-time.
  • What’s the “Master” and “Controlled” outlets labeled on the UPS?
    • The “Master” and “Controlled” outlets are not usual on a UPS; some UPS and power boards have them. They are also on power strips. 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. Having electronics plugged in the “controlled” outlet also saves devices still drawing current even though they are off.
  • Does the safe shutdown feature work for NAS equipment too or other IT items besides a server? Is their third party software?
    • 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.
  • How many outlets should I be looking for on a UPS?
    • Calculate total wattage of all equipment you want to
      Protect. Don’t bother with electronics like LCD screens. Then work out what run-time you require to keep the equipment running before shutdown.

      • E.g 15 minutes run-time…. This will give you your size of the UPS. The larger the UPS, the larger number of Outlets.

UPS Backup of Computers Scenarios

Scroll down the bottom of the page to the section called UPS Hardware backup options. Below is a pretty hefty server and a desktop utilizing a APC Smart-UPS

DC to Watts Conversion and Watts Lost Table
Note: PSU is Power Supply Unit… This is what you power cord into and typically fails upon a power surge. We get many calls for UPS battery backup support when this happens because the server is completely down.

Computers Usage Example

Cost Per Year

UPS Backup Hardware Options

Baseline Server Option

Second Tier

  • APC Smart-UPS 1500VA – 2 servers, 2 switches – $500
  •  

Third Tier

  • APC SMX3000LV – Better, remote management, handles more servers, and remote in function.  Note: requites power reciprocal l5-30r – $1400

Basic Power Distribution Unit (PDU) vs a fancy PDU

How important is a 2.9kW Single-Phase ATS / Metered (Switched PDU) PDU, 120V Outlets (24 5-15/20R, 1 L5-30R), 2 L5-30P, 2 10ft Cords, 2U Rack-Mount, TAA from some company like Tripplite in a small server environment? We are talking 2 – 3 servers plus some routers and switches…

There is a very big difference between a PDU and ATS. A PDU just provides spots to plug in power cables. A fancier one will measure total power draw, or even on a per outlet basis. It may be networkable. The most advanced allow individual power out control, so you can remotely power cycle a device, or power on, or power off.

Fancy PDU – 2.9kW Single-Phase ATS / Metered PDU, 120V Outlets

An ATS is an Automatic Transfer Switch. It is designed to take power input from 2 separate sources, and use them to feed power to devices that have just a single power supply. An ATS can be used to take power input from two separate UPS, or UPS and utility power. I have several pieces of equipment with only 1 power supply, so this is a way to keep them running in event of UPS failure. I can’t tell you how many times I have had a site go down because the battery in a UPS failed. Last time was just a few weeks ago for a UPS that was several years old, but was just put into service maybe 3 months ago.

A UPS can protect you from a failure in utility power, but for single corded equipment you need an ATS to protect you from UPS failure.

Tripplite SmartPro LCD 120V 1500VA 900W

Tripplite SmartPro LCD 120V 1500VA 900W. This will last five minutes tops w/ 3 servers.

Maybe you need a fancy PDU, and maybe you don’t. You certainly need a UPS, but my guess is that we may only get 5 minutes of runtime (it will be less runtime with age) from the UPS like…

  • Tripp Lite SmartPro LCD 120V 1500VA 900W Line-Interactive UPS, AVR, 2U Rack/Tower, LCD, USB, DB9 Serial, 8 Outlets
    • 3 Servers Max, better for 2
  • Tripp Lite UPS Smart 3000VA 2880W Rackmount AVR 120v $1000
    • More ideal for 3 or 4 servers.

 

Tripp Lite Horizontal PDU Basic 120V 2.9kW

Basic PDU – Tripp Lite Horizontal PDU Basic 120V 2.9kW

Basic PDU, A basic power strip can work in place of a basic PDU.

  • Tripp Lite PDU Basic 120V 2.9kW 30A 5-15R 24 Outlet L5-30P Horizontal 1URM – horizontal rackmount – power distribution unit – 2.9 kW

 

For best UPS battery backup support results, get a fancy PDU with ATS feature and a couple UPS in case one fails; make sure those batteries last more than five minutes.

Additional Resources

 

Power Consumption and UPS Battery Replacement Tips

https://outervision.com/power-supply-calculator

 

UPS Battery Backup Support Summary

There you go.  You went from no knowledge of your power consumption and power backup to being an expert.  Congrats!

  • Need a rack enclosure cabinet??  Check out…
    • Tripp Lite 18U Wall Mount Rack Enclosure Server Cabinet Side Mount Wallmount
      Rack – cabinet – wall mountable – black – 18U – 19″        $800

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