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UPS Vs PSS (Dedicated CCTV Power supply switch)

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Hello friends.

Newbie here, with no electronics experience , so some “support” please. ☺

Installing in my house and garage a Sannce 9 cameras system.

UPS or PSS? I've tried it on an old 300W UPS having wired a large car battery to it and after 5 minutes cut out. Only the router and the WIFI modem were connected. I keep reading that UPSs are for giving you the time to turn off the Desktop and not much else. Second why we increase the Voltage to 220 and then drop it to 12V, waste of money IMHO. There are switches that do just that. Give you 12V per channel, and the battery will last longer. Interested to hear other opinions on this.

From someone with electronics Know-How please.

I’ve ordered from China £62, (Ebay, Amazon expensive with small outputs, do a Gsearch for CCTV POWER SUPPLY SWITCH they come with backup or without), an 18channel 20A, (20A in total) power switcher with a battery backup. Each channel is 1.1A X 18ch=20A. There will be no problem with the cameras drawing .5A each, what is worrying me is the DVR with the Hard disk.

1) Does anyone knows how ±many Amps the DVRs draws ? I know they don’t do too much “manual” work to use a big load, the HD probably is doing the most. Sannce ‘technical’ girls, know less than my cat…

2) In this Hyper super backup box of mine, each channel has its own protection circuit, with its own fuse etc. Now my question is: How about if I were to “bridge” in parallel 2 adjoining channels and then draw out from those two channels to power the DVR. Will it give me 2.2A or it will fry up??? The fuses are PTC (Resetable), will they stand to the challenge or would I have to solder larger fuses there? Remember I will be doubling the demand by drawing 2.2A from two channels but also doubling their strength.

3) As long I don’t draw more than the 20A maximum capacity of the transformer should I have a problem?

4) Last question: I am sure many have asked this one. What are the disadvantages, except of fumes in the house and acid on the floor, when I miss the dog…

Thank you

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you should not mess around with changing fuses unless you have qualified knowledge- that's what can start fires- generally the fuse is there to protect the cable- so a larger fuse means you should have a larger cable that can handle the larger load, a smaller cable with a large fuse could easily catch fire.

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You need to understand the concept of this power supply. It is simply a single 20A power supply with 18 parallel output feeds each protected by a PTC device. They are not fuses. They are tripped by a rise in temperature caused by overcurrent and are a slow acting device when compared with a fuse. Fuses are usually for fault protection while PTC is for dummy protection.

You can parallel the outputs up to provide greater current capability. Wire 3 o/ps together and you triple your current availability which is then fed via 3 PTC devices so protection essentially remains the same. DO NOT CHANGE THE PTC,


As long as your TOTAL load current does not exceed your single 20A power supply capability all will be good.

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Thanks guys for your comments.


It's 5 months since I've posted the question above, and I just want to say that everything is fine with my UPS in supplying the cameras, the DVR, the router and the Dish satellite internet, all that in case I get power disconnection prior to a robbery.

The only thing that went wrong was the 50mm cooling fan inside the UPS. I replaced it with a 120mm fan which runs almost silently, and also added a thermostat that if the fan goes down again and the temperature increases inside the UPS, it will cut the supply to it so it doesn't fry up.


I attach a photo of my UPS as when I bought it. Cheap as chips £62 incl Postage with DHL and + £ the battery. I don't think you can get it cheaper elsewhere, Good old China, what we'll do without them? Please don't ask me for more details, otherwise the MOD will tell me


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