Buying a UPS

How about extension cables? See all your troubles are sorted. Just get a bunch of them and use them when you need to? :D
 
The_Traveller said:
It seems you don't grasp the situation here.

The guys are telling you what you're doing is dangerous, but yet you turn a blind eye.

Things might seem perfect for the first few rounds, but boom, when least expect it, the sh*t will hit the fan.

Peace,out!
Click to expand...

Still going strong here. Neighbors are all dark, with my place running as normal :D
 
Good evening kind people, was hoping to get some input on the following:

I'm going to get an Ellies 1200w inverter like this tomorrow, spec sheet here for your reference. The SO's mother has one and it has performed flawlessly for the past 3 years. Now as far as I can tell I need to pair it with a 24v deep cycle battery, correct? EDIT: Or am I being stupid and will 2 x 12V batteries work just fine? This is where I'd like some input.

  • Where is the best place to get high capacity (100Ah+) 24V batteries for a good price?
  • And am I correct in thinking I can start off with a single battery now, and add in additional batteries at a later stage?
  • The Inverter charges at 27.4v, 10/20A (selectable). Will this limit the maximum size battery and/or number of battries I can pair it with?

This setup will be used to power 1 x 46 inch LED TV, DTSV decoder, two laptops (180w max draw), my wireless router and a few 10w LED lights (4 - 6 max). I'm hoping to get 4 hours of use out of the above, and have a generator that can keep the inverter going if need be.

Some schooling would be appreciated.
 
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TehStranger said:
Good evening kind people, was hoping to get some input on the following:

I'm going to get an Ellies 1200w inverter like this tomorrow, spec sheet here for your reference. The SO's mother has one and it has performed flawlessly for the past 3 years. Now as far as I can tell I need to pair it with a 24v deep cycle battery, correct? EDIT: Or am I being stupid and will 2 x 12V batteries work just fine? This is where I'd like some input.

  • Where is the best place to get high capacity (100Ah+) 24V batteries for a good price?
  • And am I correct in thinking I can start off with a single battery now, and add in additional batteries at a later stage?
  • The Inverter charges at 27.4v, 10/20A (selectable). Will this limit the maximum size battery and/or number of battries I can pair it with?

This setup will be used to power 1 x 46 inch LED TV, DTSV decoder, two laptops (180w max draw), my wireless router and a few 10w LED lights (4 - 6 max). I'm hoping to get 4 hours of use out of the above, and have a generator that can keep the inverter going if need be.

Some schooling would be appreciated.
Click to expand...
Not bad at all. What batteries you going to get?
 
TehStranger said:
Good evening kind people, was hoping to get some input on the following:

I'm going to get an Ellies 1200w inverter like this tomorrow, spec sheet here for your reference. The SO's mother has one and it has performed flawlessly for the past 3 years. Now as far as I can tell I need to pair it with a 24v deep cycle battery, correct? EDIT: Or am I being stupid and will 2 x 12V batteries work just fine? This is where I'd like some input.

  • Where is the best place to get high capacity (100Ah+) 24V batteries for a good price?
  • And am I correct in thinking I can start off with a single battery now, and add in additional batteries at a later stage?
  • The Inverter charges at 27.4v, 10/20A (selectable). Will this limit the maximum size battery and/or number of battries I can pair it with?

This setup will be used to power 1 x 46 inch LED TV, DTSV decoder, two laptops (180w max draw), my wireless router and a few 10w LED lights (4 - 6 max). I'm hoping to get 4 hours of use out of the above, and have a generator that can keep the inverter going if need be.

Some schooling would be appreciated.
Click to expand...
I got myself one of these.

You can run it at 1x 12v battery, but then it will only deliver up to 600w/1000va. Must set it to 10a for charging in this configuration.
If you use 2x 12v batteries in serial, then it can do 1200w/2000va. In this configuration you put it on 12a for charging.

When I bought mine, it came with a manual that explains the above. What I didn't exactly understand in the beginning, was that I need to run it on wide voltage mode and not narrow voltage mode. It fails to keep stuff on on narrow. However the manual also explained why.

So buy 1 battery now, and add more later, although as noted above, your configuration of the switches will change, depending on how you connect the batteries, again there is pretty illustrations that shows you how and what in the manual.

The stuff you want to connect, will easily run on it.
I had:
2x pcs
1x 24port gbs switch
1x mikrotik 751g
1x zyxel vdsl router
1x ubiq m5-400
1x wireless phone
on it and it was on 1 out of 4 bar load.

When I turn on TV 200w and avreceiver it goes up to 2/4 bar load.
 
Mike Smit said:
Not bad at all. What batteries you going to get?
Click to expand...

I'm not too sure yet, that's the part I'm stuck on, was hoping to get the feedback Tinuva posted above. :) So now I'll do some proper research and see what I can get.

Tinuva said:
I got myself one of these.

You can run it at 1x 12v battery, but then it will only deliver up to 600w/1000va. Must set it to 10a for charging in this configuration.
If you use 2x 12v batteries in serial, then it can do 1200w/2000va. In this configuration you put it on 12a for charging.

When I bought mine, it came with a manual that explains the above. What I didn't exactly understand in the beginning, was that I need to run it on wide voltage mode and not narrow voltage mode. It fails to keep stuff on on narrow. However the manual also explained why.

So buy 1 battery now, and add more later, although as noted above, your configuration of the switches will change, depending on how you connect the batteries, again there is pretty illustrations that shows you how and what in the manual.

The stuff you want to connect, will easily run on it.
I had:
2x pcs
1x 24port gbs switch
1x mikrotik 751g
1x zyxel vdsl router
1x ubiq m5-400
1x wireless phone
on it and it was on 1 out of 4 bar load.

When I turn on TV 200w and avreceiver it goes up to 2/4 bar load.
Click to expand...

Great, this is the feedback I was hoping for, thanks a lot!
 
KOPITE said:
Nah, have a family.

Nobody can give me a good enough reason not to use it
Click to expand...

One of the problems with "supplying" (reverse feed) through a wall socket is that you don't have any "earth leakage" protection. If for some reason wires gets exposed and/or someone touches a live conductor, he/she will get choked or even worse be killed.
 
Tinuva said:
I got myself one of these.

You can run it at 1x 12v battery, but then it will only deliver up to 600w/1000va. Must set it to 10a for charging in this configuration.
If you use 2x 12v batteries in serial, then it can do 1200w/2000va. In this configuration you put it on 12a for charging.

When I bought mine, it came with a manual that explains the above. What I didn't exactly understand in the beginning, was that I need to run it on wide voltage mode and not narrow voltage mode. It fails to keep stuff on on narrow. However the manual also explained why.

So buy 1 battery now, and add more later, although as noted above, your configuration of the switches will change, depending on how you connect the batteries, again there is pretty illustrations that shows you how and what in the manual.

The stuff you want to connect, will easily run on it.
I had:
2x pcs
1x 24port gbs switch
1x mikrotik 751g
1x zyxel vdsl router
1x ubiq m5-400
1x wireless phone
on it and it was on 1 out of 4 bar load.

When I turn on TV 200w and avreceiver it goes up to 2/4 bar load.
Click to expand...

What are you saying ?

This Inverter comes in two different models offering with one requiring 12vdc to start up and the bigger one requiring 24dc. Its not one and the same where you can choose to either use it as a 12vdc or 24dc.



TehStranger said:
Good evening kind people, was hoping to get some input on the following:

I'm going to get an Ellies 1200w inverter like this tomorrow, spec sheet here for your reference. The SO's mother has one and it has performed flawlessly for the past 3 years. Now as far as I can tell I need to pair it with a 24v deep cycle battery, correct? EDIT: Or am I being stupid and will 2 x 12V batteries work just fine? This is where I'd like some input.

  • Where is the best place to get high capacity (100Ah+) 24V batteries for a good price?
  • And am I correct in thinking I can start off with a single battery now, and add in additional batteries at a later stage?
  • The Inverter charges at 27.4v, 10/20A (selectable). Will this limit the maximum size battery and/or number of battries I can pair it with?

This setup will be used to power 1 x 46 inch LED TV, DTSV decoder, two laptops (180w max draw), my wireless router and a few 10w LED lights (4 - 6 max). I'm hoping to get 4 hours of use out of the above, and have a generator that can keep the inverter going if need be.

Some schooling would be appreciated.
Click to expand...

So to get back your question(s) , if you opting for the 600w model then you need just one 12v battery and if you going to buy the 1200w model, then you need two 12v batteries wired in SERIES ( not serial ).
You can add another string in parallel if you need more backup time.

Please keep in mind you need proper lead acid batteries not junk lead calcium.
 
The_Traveller said:
What are you saying ?

This Inverter comes in two different models offering with one requiring 12vdc to start up and the bigger one requiring 24dc. Its not one and the same where you can choose to either use it as a 12vdc or 24dc.
Click to expand...

This is what I understood from the spec sheet, however I was hoping what Tinuva was saying would be the case, and that the manual provided with the unit explains things better than the spec sheet. I'll just get 2 x 12v to pair with the unit and be done with it.

The_Traveller said:
So to get back your question(s) , if you opting for the 600w model then you need just one 12v battery and if you going to buy the 1200w model, then you need two 12v batteries wired in SERIES ( not serial ).
Click to expand...

I'm going for the 1200w model, so will just get the 2 x 12v batteries and be done with it. Any recommendations for batteries?
 
TehStranger said:
This is what I understood from the spec sheet, however I was hoping what Tinuva was saying would be the case, and that the manual provided with the unit explains things better than the spec sheet. I'll just get 2 x 12v to pair with the unit and be done with it.



I'm going for the 1200w model, so will just get the 2 x 12v batteries and be done with it. Any recommendations for batteries?
Click to expand...

Also keep in mind that you are buying a modified sine wave inverter that is only 80% efficient.
So 1200w / 80 = 960w
960w / 24v = 40Ah
if you buying 2 x 12v100ah batteries ( 100ah / 40ah = 2.5 ) , you only getting 2.5 hours of backup time, if you drain your batteries 100%. you cant drain a battery 100% , and (depending on the battery you buy ) you should only discharge it to 50%.

Im sure I confused the shyte out of you but go on, buy the unit, you putting down very little money to learn what you are actually doing.
 
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The_Traveller said:
Also keep in mind that you are buying a modified sine wave inverter that is only 80% efficient.
So 1200w / 80 = 960w
960w / 24v = 40Ah
if you buying 2 x 12v100ah batteries ( 100ah / 40ah = 2.5 ) , you only getting 2.5 hours of backup time, if you drain your batteries 100%. you cant drain a battery 100% , and (depending on the battery you buy ) you should only drain it to 50% dod.

Im sure I confused the shyte out of you but go on, buy the unit, you putting down very little money to learn what you are actually doing.
Click to expand...

You didn't confuse me at all actually, but thanks.

Your calculations for the inverter are assuming full load correct? So if the load is lower (i.e. 400w total) then it would look something like this:

400w / 24v = 16.66Ah
100Ah / 16.66Ah = 6 hours for a 100% drain

Which means draining to 50% should give me 3 hours comfortably. If load shedding is longer than 2 hours (to be safe), I plug the generator into the Inverter and go on my merry way.

Or am I wrong here?

Also your first step bringing in efficiency actually increases the potential backup time instead of decreasing it. Shouldn't it actually be the other way around? Lower efficiency will either reduce the total backup time instead of increasing it, or reduce the total capacity of the Inverter?
 
The_Traveller said:
Also keep in mind that you are buying a modified sine wave inverter that is only 80% efficient.
So 1200w / 80 = 960w
960w / 24v = 40Ah
if you buying 2 x 12v100ah batteries ( 100ah / 40ah = 2.5 ) , you only getting 2.5 hours of backup time, if you drain your batteries 100%. you cant drain a battery 100% , and (depending on the battery you buy ) you should only discharge it to 50%.

Im sure I confused the shyte out of you but go on, buy the unit, you putting down very little money to learn what you are actually doing.
Click to expand...
Seems like you confused the shyte out of yourself. You efficiency math is wrong. 1200w output will drain 1500w from the batteries i fit is 80% efficient.
 
TehStranger said:
You didn't confuse me at all actually, but thanks.

Your calculations for the inverter are assuming full load correct? So if the load is lower (i.e. 400w total) then it would look something like this:

400w / 24v = 16.66Ah
100Ah / 16.66Ah = 6 hours for a 100% drain

Which means draining to 50% should give me 3 hours comfortably. If load shedding is longer than 2 hours (to be safe), I plug the generator into the Inverter and go on my merry way.

Or am I wrong here?

Also your first step bringing in efficiency actually increases the potential backup time instead of decreasing it. Shouldn't it actually be the other way around? Lower efficiency will either reduce the total backup time instead of increasing it, or reduce the total capacity of the Inverter?
Click to expand...
Ok great that you understand all this. I just assumed because of you initial question on the inverter side.

Yes your calculations are correct.

Isnt that what I said , that the inverter is not 100% efficient , and only 80% , which would mean you wont be able to load up to 1200w ( ideally even if you could load to 1200w , it is not recommended).
 
P924 said:
Seems like you confused the shyte out of yourself. You efficiency math is wrong. 1200w output will drain 1500w from the batteries i fit is 80% efficient.
Click to expand...

Ah, I thought so, same way you'd calculate a power supply's maximum draw from the wall is it's 1200w and 80% efficient.

/Glad for not having the shyte confused out of myself.

The_Traveller said:
Ok great that you understand all this. I just assumed because of you initial question on the inverter side.

Yes your calculations are correct.

Isnt that what I said , that the inverter is not 100% efficient , and only 80% , which would mean you wont be able to load up to 1200w ( ideally even if you could load to 1200w , it is not recommended).
Click to expand...

High school was a long time ago, I just figured I'd double check things here before parting with money. :whistle:

I just think your step 1 on the efficiency was a little unclear is all.
 
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Eskom can kiss my.....

Sooooo tired of the mind-numbing boredom during Eskom load shedding with no PC nor TV to keep myself amused! Problem solved, bought a Crystal Intellipower 4, 2000VA/1200W, plug n play UPS/inverter. Cost R6579

Test 1: Switched off the wall plug with PC, modem, monitor, PC sound system and laser printer (on standby), plugged in. Charged my phone and ran a table fan from time to time too. Load was only 1 of 4 bars indicated, with occasional spikes to 2 bars. It easily ran past the usual Eskom 4 hour load shedding mark and when I switched the power back on after 5 hours, still had 3 bars charge left.

Allowed to fully recharge.

Extreme test 2: Added to the above PC load, my TV, Hifi amplifier, DSTV decoder, Bluray player and a multimedia player (on standby). It showed the load at 2 bars and ran for 3 hours 50 minutes before beeping for low voltage on 1 bar charge and switched itself off.

I have it permanently linked to my PC atm and the switch-over is fast so PC doesn't even feel it, no reboot needed. I've commissioned a new lounge TV cabinet that can take the inverter, main reason is to prevent the DSTV decoder rebooting which is the biggest waste of time. This thing's fast. Lightening caused the power to briefly glitch, I picked it up by the lights dimming but no other appliances e.g. clocks "saw" it. Nevertheless, the UPS kicked into backup mode Immediately and switched back into standby a few seconds later when it realised it was a false alarm. Love this thing!

I am massively impressed. :)

Can be seen here: http://www.maidenelectronics.co.za/pINT4/CPe-Crystal-Intellipower-4--2000va-1200w-Long-Backup-UPS-w-2-x-100Ahs.aspx
 
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TehStranger said:
Ah, I thought so, same way you'd calculate a power supply's maximum draw from the wall is it's 1200w and 80% efficient.

/Glad for not having the shyte confused out of myself.



High school was a long time ago, I just figured I'd double check things here before parting with money. :whistle:

I just think your step 1 on the efficiency was a little unclear is all.
Click to expand...
dafuq happened to my posts above ? anyway ...

Let me clear this up a little if you don't mind. . . I was just doing some rough calculations but if we have to really calculate the system you are opting to buy ... then it would be as follows ...

your load / efficiency / vdc
400 / 0.80 / 24
= 20.83 Ah required ( ignoring dc curves)
 
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Tinuva said:
No you are wrong. The manual disagrees with you.

It specifically shows, how this very exact model can run in both 600w or 1200w configurations, depending on how the batteries are connected to the inverter. It doesn't have anything about the 600w model.

It very specifically states, if you have 12v battery configuration, eg. 2x 12v batteries in parrallel, it will operate up to 600w. If the battery connection configuration is 24v, eg. 2x 12v batteries in serial, it will operate up to 1200w.

If he buys the 600w model, he will be limited to that. If he buys the 1200w model, he can start out with 1 battery and upgrade later to 2.
Click to expand...

What manual? The spec sheet linked shows 2 models, with the charging current selectable, but the 1200W model lists only 24V as an input option.

The_Traveller said:
Errr no, I didn't confuse the shyte out of myself , and you're just trying to make this more complicated.
Click to expand...

Well, inverters are rated by their output power, so this inverter is capable of delivering 1200W output. At 80% efficiency, that equates to 1500W draw from the batteries and 300W loss. In your equation, your inverter is 125W efficient.

1500w/24V = 62.5A

If you draw 400W on the AC side, then the inverter will draw 500W from the batteries:

400/0.8 = 500W.
500/24 = 20.93A
So 100Ah batteries should last 4.8 hours, but you only want to go to max 50% of that = 2.4hours (50% DoD)
 
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