Ups

[kiepie]

Hi all

My UPS just gone (no longers keep the pc runing if the power fails)

Where can I buy a reliable one? How long do they supply power?

I heard there are two different kinds.

One where the battery supplies the power 24/7 and it is only charge by the electricity.
The other one where you still get your normal electricity via the UPS and the batery only kicks in after a power failure.

Don't know if this is true.

 

[Mux]

how stuff works

I find for general everyday type questions the follow site very useful - for example: "How does a computer's uninterruptible power supply (UPS) work?"
A more technoical document from APC gives different options.
And perhaps 1 more site (nice tool): MGE UPS systems

 

[rabbiddog]

All you need to do is get your UPS serviced. It probably has a bad battery. MGE and other places can test it for you.

 

[kiepie]

It must be the battery, had it for longer than 5 years.

New ones start from R400 at matrix, phoned them today.

 

[Gunny]

Normally you can just change the batteries in the UPS and have it up and running again. Most use 2 x 7Ah 12V batteries which cost about R100 each.

 

[kiepie]

Any idea were I can do this? DIY or what??

 

[rabbiddog]

You can change, and/or charge the battery's your self. To charge them just disconnect them and use a trickle charger on each battery in turn.
In a UPS if the battery charge level is below a certain level (I think it is around 30%) the UPS will not auto charge them and they need to be charged manually.

 

[ambo]

If the batteries are over 5 years old then I wouldn't bother with doing a trickle charge or any of the other battery refresh tricks.

Last time I bought the Sealed Lead Acid Batteries that are used in most small UPS's they cost R60-ish and you should only need one or 2 so its really not that much of an outlay.

If you are comfortable opening up your computer or toaster and doing basic repairs then it probably is a DIY job. Open the cover of the UPS but remember that the entire circuit should be assumed to be running 220v at ALL times (even if the batteries are disconnected) You'll proably find some spade connectors that need to be pulled of the batteries and a couple of screws to remove the clamps holding the batteries in... swap old for new and put everything back together. Usually a good idea to make sure that the new batteries are charged when you put them in - they are supposed to be stored (ie sold) fully charged but check anyway.

The maintainance contract on most large UPS's requires battery replacement about every 2 years - think that 5 years is quite a decent haul for a set of batteries.