How to determine how long a UPS will power a router

[darth_626]

Hi all!

 

I would like to ask for some help. In South Africa we are currently experiencing a lot of power outages so I would like to get a ups to power my router while it’s out. 
 

I would like to ask how I would calculate the length of time a ups would power my Network setup. 
 

Thank you all for your time and I hope you have a wonderful day!

[Electronics Wizardy]

look at chart in the ups docs?

 

What is wh of battery? How much power are you pulling from the ups?

[minibois]

What UPS do you have? What is your PC build like? What are you doing on your PC (as doing gaming, will drain it more than just YouTube for example)?

 

Most UPS systems will have a 'runtime graph' to show how long it will run at certain watt usages. Just simply looking at how much your PC uses, you will see how long it will run.

 

EDIT: ope, looks like I accidentally read PC instead of router.. welp.. Point still stands I guess. What router and what UPS?

[191x7]

Most modems/routers draw 20W to 30W.

If a cheap UPS has a rating of 450VA 300W and it holds a 300W load for 5 minutes, I would deduce that it would hold 30W for 50 minutes.

[darth_626]

I just don’t know what to look at in terms of values. Looking to buy a ups. 

[Electronics Wizardy]

Just now, darth_626 said:

I just don’t know what to look at in terms of values. Looking to buy a ups. 

how much power does your devices that need to be powered use? Get a meter to find out if you want a accurate number.

 

Look at the rating of the ups and it will tell you how long.

[W-L]

19 minutes ago, darth_626 said:

Hi all!

 

I would like to ask for some help. In South Africa we are currently experiencing a lot of power outages so I would like to get a ups to power my router while it’s out. 
 

I would like to ask how I would calculate the length of time a ups would power my Network setup. 
 

Thank you all for your time and I hope you have a wonderful day!

What is the networking hardware that you will be using? For example a unit such as this is capable of 330W but if your networking equipment only uses around 30W it can last around 110mins or just under 2 hours. You will need to get a unit that is specific to your region. 

 

https://www.apc.com/shop/us/en/products/APC-Back-UPS-BE600M1-600VA-120V-1-USB-charging-port/P-BE600M1

 

https://www.apc.com/products/runtimegraph/runtime_graph.cfm?base_sku=BE550G&chartSize=large

[mariushm]

Figure out how much power the device consumes.

 

Look on the power adapter and see what it says on it.  If it says 12v 1.5A, then that power adapter can supply up to 12v x 1.5 = 18 watts. If there's nothing written on the power supply, then maybe buy a power meter (go on amazon.de or other sites for EU plugs) and determine the average power consumption over a minute or two.

 

The UPS takes 10.8v .. 14v from internal battery and creates 230v AC which then powers devices plugged into UPS.

As this conversion is not 100% efficient, simply multiply that value you measured by 1.1 - 1.25, to be on the safe side.

You now have the maximum watts which are taken from the battery.

 

For example, say your devices consume 30 watts in total on average, so estimate 30w x 1.25 = 37.5 watts.

 

Now divide the voltage of the battery by that number and you get 12v / 37.5w = 0.32A

 

So now you can look at typical batteries found in UPSes

 

7.2 Ah : https://b2b-api.panasonic.eu/file_stream/pids/fileversion/3535

You can see the 0.36A curve going up to 20 hours

 

12Ah : https://b2b-api.panasonic.eu/file_stream/pids/fileversion/3537

This does 20 hours at 0.6A , more at less current.

 

and so on ...