Buying a UPS

Ok, just send an email to info and sales. Let's see if I get a response ...
 
It all boils down to the batteries at the end of the day. A typical consumer UPS you buy from Incredible Connection or Computer Mania is not going to be able to run anything for any significant length of time. It doesn't help having a 1KW UPS if your batteries are only 7 amp hours.
 
The problem with affordable UPS batteries is that they are not proper deep cycle batteries. If you discharge them more than a few percent, they won't last a dozen cycles.

To all of you using deep cycle batteries and doing calculations on how long they will last, please use a discharge rate of 30% up to maximum 40% if you would like those expensive batteries to last at least a few years of daily use.

The UPS battery charger circuit will have a current limit, say 5 Amps. So even if you connect a large battery, it will still charge it no problem, but it will take many hours. The question is whether the cheap charging circuit can handle a constant charging load for 12 or more hours.
 
Mike Smit said:
Okay - now I don't know what is going on.

I got this UPS (and it's not 1000W, it's 1400VA/840W - checked up on the net) from my electrician because he is taking so long with getting my Tedelex Intellipower inverter back to me.
This UPS came with 2 x 7.2Ah batteries in it. He pulled them out and extended the battery leads so I could hook it up to deep cycle batteries.
He told me it was 12V UPS, so I only connected up one of my new Ellies 102Ah batteries. I did this yesterday and left it charging until just now. With nothing connected the battery measured 13.54V.

I now wanted to test it so I know what I am in for come load shedding. I pulled the power from the UPS and it got about 2 mins in and started beeping like mad (indicating low battery). I plugged the power back in, and removed the charge leads from the battery. Battery measured 12.6V. In 2 MIN!!

I had a chat with my electrician now on whatsapp and asked if he was sure if it was a 12V UPS as this is just dodgy. After all it came with 2 x batteries inside, so suspected it might (just might) have been 24V. He is pretty sure, but not 100% sure.

I am pulling 240W by the way.

I purchased these Ellies batteries because the 2 x 70Ah batteries I had hooked up (in parallel) were only giving me 40 mins or so, with only a 30W draw on the system (router and ADSL modem). So I figured my batteries were old and shot. But now with a brand new battery, it is even worse.

The UPS is an Eco 140. http://www.pssdistributors.com.au/eco-1400va-line-interactive-ups

Any ideas people?

I am on the verge of just taking the plunge and purchasing a 1200W inverter like I had and be done with it. Waste of cash though if I can get my Tedelex back ASAP. Other problem is I cannot find anyone in Edenvale that stocks any.

EDIT: For the 2 mins the UPS was on battery, the battery was buzzing very loud.
Click to expand...

I have one of those PSS UPS's as well, although only the 600VA one. I have it on my PC, but it is set to turn off the PC after 30 seconds (it should actually be larger for the PC, but only realised it after I got it at home, will get a bigger one and use this for the modem). What I have noticed with it is during load shedding, with the PC off, the back of the UPS gets very hot where the transformer is. This is only supplying limited power to the PC while off, so I think it is very inefficient. I don't know if the APC ones are more efficient when running off the battery?

This UPS is rated for 360W, tried to run the 42" TV and home theatre off it but it only lasted 10 minutes. I have had my ADSL modem on it for at least 3 hours during load shedding and it was still running.
 
So you guys reckon something like this is a no no?

Want to be able to run my 32" LCD TV/DSTV Decoder/HP Microserver for 2-3 hours.
 
Gaz{M} said:
The problem with affordable UPS batteries is that they are not proper deep cycle batteries. If you discharge them more than a few percent, they won't last a dozen cycles.

To all of you using deep cycle batteries and doing calculations on how long they will last, please use a discharge rate of 30% up to maximum 40% if you would like those expensive batteries to last at least a few years of daily use.

The UPS battery charger circuit will have a current limit, say 5 Amps. So even if you connect a large battery, it will still charge it no problem, but it will take many hours. The question is whether the cheap charging circuit can handle a constant charging load for 12 or more hours.
Click to expand...

This exactly why you are far better off getting yourself proper deep cycle batteries (at least 102AH each), a proper pure sine wave inverter and a decent battery charger and basically building your own system from scratch. It's going to be far more durable, last longer, and be more effective than any consumer-grade UPS out there.
 
deweyzeph said:
This exactly why you are far better off getting yourself proper deep cycle batteries (at least 102AH each), a proper pure sine wave inverter and a decent battery charger and basically building your own system from scratch. It's going to be far more durable, last longer, and be more effective than any consumer-grade UPS out there.
Click to expand...

Would it be wise to get a battery charger already incorporated into the Inverter or a separate unit?
 
Okay, I figured out this ECO140 UPS is indeed 12V and not 24V. I wired up the batteries in series, attached the UPS and boom boom. Thing sound like it was going to blow my house up. Back to 12V it is :)

Not working though. Stupid thing cannot handle 250W and just kills the battery for whatever reason.

Asked the electrician to return my Tedelex inverter and I will find someone else to do the repairs. Who though is the question...
If I can find someone selling an inverter/charger I will just buy one. No-one got stock though. So annoying.
 
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Mike Smit said:
Okay, I figured out this ECO140 UPS is indeed 12V and not 24V. I wired up the batteries in series, attached the UPS and boom boom. Think sound like it was going to blow my house up. Back to 12V it is :)

Not working though. Stupid thing cannot handle 250W and just kills the battery for whatever reason.

Asked the electrician to return my Tedelex inverter and I will find someone else to do the repairs. Who though is the question...
If I can find someone selling an inverter/charger I will just buy one. No-one got stock though. So annoying.
Click to expand...
I started a thread called UPS/Inverter support thread, yeah and some people kinda mocked me but f\/ck em, theres a contact number there of a company who does repairs. Teljoy gave me the number as they were the first ones to sell the Tedelex Intellipower units a few years back.

http://mybroadband.co.za/vb/showthread.php/666839-The-UPS-Inverter-support-thread/page2
 
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Advice on inverter, powered by 2 x batteries

I have a couple of large 105 AH deep-cycle batteries which I keep fully charged using a C-Tek Multi XS 25000 intelligent charger.

I would obviously need an inverter to provide ~230 VAC from the 12V battery supply

(I guess I would need a pure sine wave inverter?)

Any recommendations for a good quality inverter that can be bought online? (the klein dorpie I live in means I will have to look further afield, as in an online purchase, and courier delivery)

What would be the inverter specifications (e.g. is a pure sine wave needed?)

I would need to use those batteries to keep 1x laptop, plus 1x Desktop PC, as well as my Billion 400G ADSL Router running for a few hours?

And would the 2 x 105AH deep-cycle batteries, in good condition, and when fully charged & connected in parallel ( ... so effectively a 12 Volt, 210 AH DC supply) be enough to meet my needs above?

The PC is a pretty standard Desktop PC running Win 8.1, not high spec, and not used for gaming / fancy graphic design, so the PC would not draw excessive current

I know that the laptop battery would last me almost an hour or so (laptop battery is quite new), but what running duration I expect when using the PC PLUS the Laptop from an inverter?
 
atomcrusher said:
I have a couple of large 105 AH deep-cycle batteries which I keep fully charged using a C-Tek Multi XS 25000 intelligent charger.

I would obviously need an inverter to provide ~230 VAC from the 12V battery supply

(I guess I would need a pure sine wave inverter?)

Any recommendations for a good quality inverter that can be bought online? (the klein dorpie I live in means I will have to look further afield, as in an online purchase, and courier delivery)

What would be the inverter specifications (e.g. is a pure sine wave needed?)

I would need to use those batteries to keep 1x laptop, plus 1x Desktop PC, as well as my Billion 400G ADSL Router running for a few hours?

And would the 2 x 105AH deep-cycle batteries, in good condition, and when fully charged & connected in parallel ( ... so effectively a 12 Volt, 210 AH DC supply) be enough to meet my needs above?

The PC is a pretty standard Desktop PC running Win 8.1, not high spec, and not used for gaming / fancy graphic design, so the PC would not draw excessive current

I know that the laptop battery would last me almost an hour or so (laptop battery is quite new), but what running duration I expect when using the PC PLUS the Laptop from an inverter?
Click to expand...

The first thing you need to do is work out how much power your devices are going to draw if you run them all together, which you can usually check by looking at the back of your device or the transformer.

So for example:

Laptop - 90W
Desktop PC - 500W
ADSL Router - 12W

Total - 602W

Your total power draw will be 602W (per hour) which means you will need an inverter with a power rating of at least this, but realistically you need to consider a buffer or margin. So let's say a 1 kilowatt inverter will be sufficient and give some margin to add more devices.

On the battery side of things, watts = voltage x amps, which means that your 602W of power draw will consume about 50 amps of current per hour at 12V. However deep cycle batteries should not be discharged less than 50% of their charge, so effectively you really need a 100Ah battery just to run at this power usage for 1 hour without discharging the battery to less than 50%. If you want to run a system of this power usage for 3 hours you would need 3 x 100Ah batteries, and so on.

So really, you need to either get more batteries, or use less power.
 
deweyzeph said:
The first thing you need to do is work out how much power your devices are going to draw if you run them all together, which you can usually check by looking at the back of your device or the transformer.

So for example:

Laptop - 90W
Desktop PC - 500W
ADSL Router - 12W

Total - 602W

Your total power draw will be 602W (per hour) which means you will need an inverter with a power rating of at least this, but realistically you need to consider a buffer or margin. So let's say a 1 kilowatt inverter will be sufficient and give some margin to add more devices.

On the battery side of things, watts = voltage x amps, which means that your 602W of power draw will consume about 50 amps of current per hour at 12V. However deep cycle batteries should not be discharged less than 50% of their charge, so effectively you really need a 100Ah battery just to run at this power usage for 1 hour without discharging the battery to less than 50%. If you want to run a system of this power usage for 3 hours you would need 3 x 100Ah batteries, and so on.

So really, you need to either get more batteries, or use less power.
Click to expand...
Great informative answer! Many thanks deweyzeph
 
atomcrusher said:
Great informative answer! Many thanks deweyzeph
Click to expand...

No problem. This should highlight how hopelessly underpowered the average consumer UPS is for running anything for any length of time. Your average consumer UPS doesn't have anywhere near the necessary battery power to act as a replacement power supply during load shedding. At most they will give you a few minutes to power down your devices gracefully.
 
deweyzeph said:
No problem. This should highlight how hopelessly underpowered the average consumer UPS is for running anything for any length of time. Your average consumer UPS doesn't have anywhere near the necessary battery power to act as a replacement power supply during load shedding. At most they will give you a few minutes to power down your devices gracefully.
Click to expand...

Also, the inverter is not very efficient, so you lose a good chuck of battery power in the inverter. Thus even more batteries.

If you really want to run a lot of stuff of a ups you need to spend a lot of money on it. It might be cheaper to run it off a generator.
 
furpile said:
Also, the inverter is not very efficient, so you lose a good chuck of battery power in the inverter. Thus even more batteries.

If you really want to run a lot of stuff of a ups you need to spend a lot of money on it. It might be cheaper to run it off a generator.
Click to expand...

Ja, forgot to mention that. You can probably add about 15% to 20% to those figures for inefficiencies depending on the make and model of the inverter, although it's small enough to ignore to get a rough idea of what sort of battery power you need. Bottom line is you can never have enough batteries.
 
So much for powering my adsl router tonight, after an hour Telkom died. Seems the DSLAMs batteries are worst than my UPS. Back to expensive 3G :cry:

At least my LED light is going strong still on the UPS.
 
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