b.eggersglusz

Reputable
Mar 26, 2018
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Hello currently I'm having an issue figuring out a valid UPS system for my network.

I live in South Africa where currently we are experiencing load shedding. Our country can't keep up with demand so we have 2 hour periods everyday where there is no power. So im im need of a solution to power my network during the 2 hours.

We have dish internet so we would need the dish and router to last the 2 hours.

My network configuration is Ubiquity 30dBm dish > Mikrotik radio > Ethernet > POE > Wireless Access Point (router)

We currently have 2 generic computer UPS with brand new batteries. Wondering if 1 or both can be daisy chained to power the system

if you need the POE adapter specifications or anything let me know.

not sure what the power draw is. maybe i could just try and see if it works. but not sure if it'll damage it
 
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So basically a generator is a bit over the top just to run the WIFI, i know we can run other stuff but the fuel cost etc doesnt make it worth it, We simply have 2 UPS's that both have a 12volt battery in them at 7.2ah

The equipment we need to power is
router - 9v - 600ma
dish/poe - 24v 800ma

Now we do have larger batteries, we have 100ah 12 volts and 90ah 12 volt batteries.

But im not sure if its going to be a problem that the dish requires 24volt output. Is it possible to daisy chain batteries then run them through the inverter on the UPS or does electricity just not work like that.

In south africa our wall voltage is 230v at 50hz

Basically the battery method is the best choice for me. We have other batteries, and if need be I...
It depends on your UPS. Mine actually show the usage so you can look as you add equipment. So you could see the power needed by plugging them into your current UPS.

So there are 2 basic numbers you look for. The first is the VA rating. This is kinda the same as watts. What you need to do it add up the watts on each piece of equipment. This is the maximum power it can deliver but it does not show how long it will last.

The same VA UPS can run very different times. This is all based on how large the batteries are. You need to dig around and find what actual batteries it uses. Say one ups has a 12v 10ah batteries and another with the same va rating has 2 12v 10ah batteries the second would last 2 times even though they have exactly the same VA number.

Previously I always looked at the weight of the unit. Batteries are heavy so the more it weight the longer it lasts.

So to get a idea how much battery you need to do some math. First find the amps you equipment needs. This is always marked on the power supplies. Now you must convert the voltage to match the battery. If for example you have 120 volt power and the UPS uses 12 volt batteries you need to multiply the amps by 10.

So a 1 amp device at 120volts will use 10 amps of power at 12 volts. So now lets say your USP uses 12volt 10ah batteries. This would mean a 1amp 120 volt device would last 1 hour on a 12volt 10ah battery so your unit would need 2 batteries to last 2 hours. This is a very simple example and you really need to allow extra battery power because of inefficiency and as the batteries age they last less. I think your power is 240 volts so you must take that into account.

Now this gets expensive fast. Some UPS can take external battier packs. Now some people connect somethings like batteries for fishing trolling motors. These are like car batteries designed for constant drain. You can get a 100ah battery which would be the same as 10 10ah ups battery. The problem is you will likely damage the charging circuit in the UPS over time since it has to run much longer to recharge these large battery

What I would do is buy a generator. It is important you buy one of the newer sign wave generators. A UPS does not work well on normal cheaper generator. What I would do is buy a smaller UPS that can last say 15 minutes. This would give you time to go out and start the generator and unplug the UPS from the city power and plug it into the generator. There are of course fancy generators that switch over automatically but it adds to the costs.
 
Last edited:

b.eggersglusz

Reputable
Mar 26, 2018
29
3
4,535
So basically a generator is a bit over the top just to run the WIFI, i know we can run other stuff but the fuel cost etc doesnt make it worth it, We simply have 2 UPS's that both have a 12volt battery in them at 7.2ah

The equipment we need to power is
router - 9v - 600ma
dish/poe - 24v 800ma

Now we do have larger batteries, we have 100ah 12 volts and 90ah 12 volt batteries.

But im not sure if its going to be a problem that the dish requires 24volt output. Is it possible to daisy chain batteries then run them through the inverter on the UPS or does electricity just not work like that.

In south africa our wall voltage is 230v at 50hz

Basically the battery method is the best choice for me. We have other batteries, and if need be I can hook the larger car batteries up to a battery charger we own as to not damage the UPS the UPS just needs to be used as the inverter/adapter. But our biggest problem is the dish using 24v @ 0.8ah Again not sure how electrcity works but would it just using double the amps on a 12v? so 24v 0.8ah would just turn into 12v @ 1.6ah?
 

kanewolf

Titan
Moderator
So basically a generator is a bit over the top just to run the WIFI, i know we can run other stuff but the fuel cost etc doesnt make it worth it, We simply have 2 UPS's that both have a 12volt battery in them at 7.2ah

The equipment we need to power is
router - 9v - 600ma
dish/poe - 24v 800ma

Now we do have larger batteries, we have 100ah 12 volts and 90ah 12 volt batteries.

But im not sure if its going to be a problem that the dish requires 24volt output. Is it possible to daisy chain batteries then run them through the inverter on the UPS or does electricity just not work like that.

In south africa our wall voltage is 230v at 50hz

Basically the battery method is the best choice for me. We have other batteries, and if need be I can hook the larger car batteries up to a battery charger we own as to not damage the UPS the UPS just needs to be used as the inverter/adapter. But our biggest problem is the dish using 24v @ 0.8ah Again not sure how electrcity works but would it just using double the amps on a 12v? so 24v 0.8ah would just turn into 12v @ 1.6ah?
With 100Ah batteries, you should be looking around at solar or off-grid websites. You need a charger/maintainer that can deal with that type battery.
Since your batteries aren't uniform, I wouldn't recommend series wiring (24VDC), but parallel wiring. Then use DC to DC POE injectors for your POE hardware.
These guys have many options -- https://tyconsystems.com/products/tycon-power/poe-injectors/dc
 
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