UPS Backup Power

Opinions on Network Equipment and UPS Backup for the appliances
When installing network equipment is it user requirements, best practice or common practice to instigate the use of a UPS to cope with short term power outage eg 1-20mins,
I know their are many variables to this subject such as power outage frequencies or reliability of power but personally I have UPS on my Router, Switch and POE AP but I feel that if I recommend to family to invest in a UPS it is just another device to go wrong.
Any thoughts?

The power cuts where I live generally last a couple of hours.

I have not had a problem with routers loosing power.

There is also the problem of powering whatever devices use the internet connection.

A mobile phone will usually work during a power cut.

UPS batteries generally need to be replaced every few years.

We don't very often have power cuts and when we do we can live without the Internet (and can usually use mobiles). For most people an occasional outage isn't worth the hassle and investment.

I have a small APC UPS on my kit and find it handy. It's over 7 years old now and the batteries are still showing as good. It also cleans the mains and emails me when I get "brown outs" which occur a few times a year on our supply. Personally I get good use from it, and would replace it if it ever stopped working.

I have the computer and all the networking boxes supported by a UPS, power cuts are never planned and having a UPS it means I can tidy up what I am working on eg a photo edit or transmitting data and shut the system down in a controlled maner.

I have an APC UPS for my 4g modem, router, and PoE switch. Since all three devices run off wall transformer blocks they are not particularly fussy about the quality of power they are given. With this in mind you are well able to use a "stepped or modified" sine wave UPS rather than the more expensive "pure" sine wave models.

You will find that your router and switch will use about 5-10W each so a UPS with a modest wattage or VA rating is perfectly good. All UPS suffer poor efficiency when very lightly loaded. Imagine a few low power devices fitted to a 1000W UPS - you will lose more power than it uses. Getting a UPS with just a few hundred VA rating will be fine for small devices.

One thing to consider is this... do all the devices run off a 12V transformer? If so, it is MUCH more efficient to get a 12V DC inverter which will plug into the mains to charge its batteries when the mains is present and deliver 12V DC to its outputs. You would then connect your router etc directly to the 12V DC inverter. Something to look into. Ask about this on any camper van/houseboat/RV forum and you will get more details.

As for the batteries in models such as the APC Back-UPS devices you should get a good five years of light use out of them before the batteries begin to degrade. For non-commercial equipment that does not need comprehensive warranties, once the original batteries fail a battery test you can readily replace them with generic 12V AGM batteries of the correct type from brands such as Yuasa.

There are lithium alternatives for a single device where you have a small LiFePO pack fed from a small lithium charger going into a 12V DC output board going into your device. Something like this... https://www.youtube.com/watch?v=IlEnEn7ptmc

I recently replaced my UPS battery. The UPS is an APC ES 700, now with a slightly larger battery (9Ah instead of the 7Ah UPS sell it with). As DanielCoffey67 posted they are horribly inefficient at low load. Mine is set up to keep my FTTC modem, my router and my mail server (a low-power Eco server) running. Total load is about 25w and the software claims a run time of nearly 15 minutes. At that point the server will shutdown so presumably the modem and router would eventually follow suit a minute or two later.

It's enough to protect against brief glitches and circuit breaker trips (when someone is home to reset the breaker) but not enough to see you through a major power outage.

Edited by Andrue (Mon 03-Feb-20 21:59:28)

KISS, for general home use it's just not worth fitting to a friends/relatives network unless they ask for it.

In reply to a post by thomaswarne01:

Opinions on Network Equipment and UPS Backup for the appliances
When installing network equipment is it user requirements, best practice or common practice to instigate the use of a UPS to cope with short term power outage eg 1-20mins

User requirements. If a user doesn't require things to function in a power cut then nothing else matters regardless of what 'best practice' may be.

If, however, they want to be able to continue to use the internet during short power outages or they want to protect against a risk of data corruption on disks and storage devices due to a sudden loss of power they need a UPS.