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Computer UPS for home lighting!

21 posts · originally from https://geek.digit.in/community/threads/computer-ups-for-home-lighting.130809/

khmadhu
khmadhu Original post #1
Aug 13, 2010 at 8:32 AM
Hi,


Nowadays in Bangalore power cuts happening more, so I decided to buy a UPS which will benefit for both my computer and lighting.
but this costs more around 7-8K to give power to full house, my budget is tight 2.5k , so though :idea: of doing some innovative in home.

my plan is.

To buy an PC UPS like intex 1kva and give connections to only 2 lights(20w powersaver lights), and sometimes just a laptop.

if this gives around atleast 1 hr backup then its sufficient.

and also I need to setup 2way lighting, what are the other requirements for this..?
so can this be done.. what u guys say.?

please this is urgent need to buy tomoro..
gagan007
Aug 13, 2010 at 9:17 AM
no can do :)

1kva UPS in 2.5K is impossible!
P
pimpom #3
Aug 13, 2010 at 11:29 AM
A 1kVA unit is overkill to power just 2x20W lights and a laptop. It's true that a high-power UPS will give you longer backup at low load, but that is only because of a somewhat larger battery, not because it has a higher VA rating.

Your total load is much less than 200VA. So my suggestion is to buy, say a 500-600 VA UPS that has provision for connecting an external battery. A 35 Ah (Ampere-hour) car battery like that used in a Maruti 800 will give you about 2 hours backup at that load.

Please clarify what you mean by 2-way lighting. Do you mean supplying the two lights automatically from the uPS when there's a power cut?
khmadhu
khmadhu #4
Aug 13, 2010 at 11:56 AM
@gagan007, 1kva intex ups is exact 2.5k including tax and 850va is 2k including tax in bangalore SP Road

@pimpom if 1kva is more then I can go for 850va right.?, but it should be extend-able so that i can connect more devices, like running mixer, additional 2 lights if necessary,another laptop etc..

2 way lighting is exactly what u thought, but i dont want to do rewiring the house, becoz we are staying in rented house,so no touching existing electric boards. but i can go for laying extra wires to the specific fluorescent light bulbs.

so can i do this by myself or i require any electrical engineer?.

well , how much A 35 Ah (Ampere-hour) car battery costs?
P
pimpom #5
Aug 13, 2010 at 1:01 PM
@pimpom if 1kva is more then I can go for 850va right.?, but it should be extend-able so that i can connect more devices, like running mixer, additional 2 lights if necessary,another laptop etc..
I'd advise against running a mixer. It uses a lot of power compared to those other things. Without the mixer, a common 600VA UPS is still sufficient even with the additional loads you mentioned.

2 way lighting is exactly what u thought, but i dont want to do rewiring the house, becoz we are staying in rented house,so no touching existing electric boards. but i can go for laying extra wires to the specific fluorescent light bulbs.

so can i do this by myself or i require any electrical engineer?.
The principle is the same as using a computer through a UPS. You just plug in the lights and the laptop to the UPS. It switches to battery power when the mains power goes off.

You can use flexible wire to string the two lights. You can put a bed switch on the line to let you switch the lights on and off as needed. Use a good quality plug, switch and bulb holders. Anchor is a good brand that's not overly expensive.

well , how much A 35 Ah (Ampere-hour) car battery costs?
I mentioned the car battery as an example of the Ah capacity. A name brand like Exide will cost at least 2.5k. But as you live in a large city like Bangalore, you can probably find a local battery for much less. And it doesn't have to be 35 Ah. A lower Ah rating will just give less backup time.
Nemes!s
Nemes!s #6
Aug 13, 2010 at 2:16 PM
Hi pimpom

continuation to this topic,if I want to power up my pc for atleast 1 hour, what would be suitable inverter or UPS and what capacity ?

Fortunately or unfortunately I'm also from Bangalore and these frequent power cuts have become pain in a$$ :-(

my pc config is in my signature
ajayritik
Aug 13, 2010 at 3:31 PM
Hi,


Nowadays in Bangalore power cuts happening more, so I decided to buy a UPS which will benefit for both my computer and lighting.
but this costs more around 7-8K to give power to full house, my budget is tight 2.5k , so though :idea: of doing some innovative in home.

my plan is.

To buy an PC UPS like intex 1kva and give connections to only 2 lights(20w powersaver lights), and sometimes just a laptop.

if this gives around atleast 1 hr backup then its sufficient.

and also I need to setup 2way lighting, what are the other requirements for this..?
so can this be done.. what u guys say.?

please this is urgent need to buy tomoro..
In Hyderabad here we get an inverter for around 1.5 k which can be useful for having two CFL's. Why don't you try the same in your city? Instead of buying UPS and then converting etc.

Just a suggestion!
P
pimpom #8
Aug 13, 2010 at 6:24 PM
Your config is not very demanding as far as power rating is concerned. A 650 VA UPS is good enough for your computer plus, say, a couple of low-power CFL lights.

As I explained to khmadhu, backup time is determined by battery capacity. For backup times of that length, an external battery type is a must. The 35 Ah battery I cited as an example should give about 1 hr of backup when it's new and in tip-top condition.

Added later: This post was in reply to Nemes!s's question.
Cool Buddy
Aug 13, 2010 at 9:54 PM
This reminds me of something. Once we had a long power cut in our house (33 hours). After around 3 hours I had used my UPS to run my water purifier for around 20 minutes. But the power cut lasted long and we were helpless the next day.
I think a 650VA UPS will easily last an hour with 2 20/18w CFLs and around half an hour on adding a fan. One can use a temporary connection like hanging bulb holders with a plug which can be connected either directly to the UPS or through an extension cord. I suggest a make do type of arrangement coz I am sure things will be alright in Bangalore soon.
khmadhu
khmadhu #10
Aug 13, 2010 at 10:36 PM
thanks all for u r suggestions... :).. will think one more time.
khmadhu
khmadhu #11
Aug 17, 2010 at 2:37 PM
yesterday I Bought microtek 800va dual battery(double power) at 2.5k, and connected.

(1) 20w CFL(in Hall) + (1) 14w CFL(in kitchen) + Laptop + modem + Belkin Wifi router.

its working fine.. :)
coolsunny
coolsunny #12
Aug 17, 2010 at 5:41 PM
^^Congrats..
But the beep sound isn't it irritating. If there is any way to stop the beep sound. Only beep sound will come when there is very low battery,as same way we can auto shut the system when battery is low.
Any idea??
khmadhu
khmadhu #13
Aug 17, 2010 at 6:15 PM
that's not too irritating.. by default in this model for every 8 seconds it will beep. and it comes down to 1 beep/sec in very low battery mode.. and i guess in that time u can shutdown(hibernate is good) the system easily.

u cant stop that.. other than tampering the board(removing a wire may work), and i guess u wont do that if its under warranty.
vwad
vwad #14
Aug 17, 2010 at 7:27 PM
I hate beep sounds like anything, but considering the advantages, its bearable :lol:
A
acewin #15
Aug 22, 2010 at 12:23 AM
@Nemes!s, how much are you ready to shell out my friend. you need to buy smart UPS, which have extendable power options, so that you can add more battery.

UPSes will not run a system for very long time, to run them longer you will need to add more battery, this option being available in smart UPS only. Its like using general inverters you see in the market.

---------- Post added at 12:21 AM ---------- Previous post was at 12:17 AM ----------

smart UPS is expensive but a a very good option.
@khmadhu, I totally understand you bro.
I have a 1100 VA APC UPS, I use it to run my broadband wireless router, runs very long almost one and half hours I guess. CFL and fans utilize very less power, hence you can use them, still power ratings of our general UPS is very low being 40% or 50%.

---------- Post added at 12:23 AM ---------- Previous post was at 12:21 AM ----------

will also add, running laptops on UPS I do not think is very good like that, better have laptop battery running for longer duration
J
Sep 24, 2010 at 9:28 PM
Just be careful not to overcharge the car battery. UPS has a built-in charger delivering about 1-2 amps so if your battery is fully discharged, it will take forever to recharge. You might need external charger with higher current capacity.

________________
Home Lighting Enthusiast
S
skvaditya #17
Dec 1, 2010 at 1:41 PM
Hi friends. I am new to this forum & found it very informative & useful.
I would like to ask a doubt. I m really not able to understand what fault is this in my UPS.
I have a frontech 600VA UPS. I am running my desktop PC & a table lamp with 9W tube.
The table lamp is of different type. It has a choke & a starter as in tubelights. When power goes off, I noticed that my PC runs easily for 20-25 min & when the battery is about to go off, its siren blows continuously as indicated in normal working of UPS. But when I run the table lamp, it runs hardly for 2-3 min & that also is switches off without any siren or warning ring. I cant understand what fault is this. Can you all give some insight over it?
Thnx in advance.
Adi
manoj_299
manoj_299 #18
Dec 2, 2010 at 1:30 AM
I have APC 650 VA UPS using it from 3 yrs. It connect to a 11w table lamp + Broadband wifi router (Huawei) + All out (Mosquito killer). It power my room with enough light to have in room during power cut and I continue my work on Laptop. It gives 2.5 hr+ light without Laptop connected. With laptop connected it gives 40 mins only (90w Laptop charger of 17" laptop)
P
pnrkumar #19
Dec 2, 2010 at 11:17 AM
Now there is a 3 CFL UPS available for 2.5k. YOu can plugin 3 CFL Lights. Very useful for home and small shops.
gagan007
gagan007 #20
Dec 2, 2010 at 11:54 AM
I have APC 650 VA UPS using it from 3 yrs. It connect to a 11w table lamp + Broadband wifi router (Huawei) + All out (Mosquito killer). It power my room with enough light to have in room during power cut and I continue my work on Laptop. It gives 2.5 hr+ light without Laptop connected. With laptop connected it gives 40 mins only (90w Laptop charger of 17" laptop)

wwwo hhho...when will I get such a USP. I earlier had a Frontech UPS, its battery went kaput, so recently I purchased an APC one. But that too gives only about 10 mins of backup to my PC :(
manoj_299
manoj_299 #21
Dec 3, 2010 at 12:56 PM
I have no PC now. I gave it to my cousin, It was PIII 1.13 ghz. It was giving 20-22 mins backup. I just keep UPS for me to power my Laptop and home. I will go for new desktop next year :)