How long will a baby UPS run my ADSL Router?

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FlashSA

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With this whole power (or lack thereof) fiasco - I was thinking about buying a cheap UPS to run my ADSL\WIFI Router off of - so that I can at least use my laptop for the 2 hours of "load-shedding"

Now does anyone know how long the UPS will last for with just the Router plugged into it? Taking into account that the WIFI AP sucks a large part of the juice. Has anyone tried this?
 
I get an hour or more.
600va

Its the only thing on that UPS.

EDIT:
last week I plugged notebook into ADSL router, and notebook battery died first :/
 
Aah that is pretty decent! What sort of price can one expect to pay for a 600va UPS? I'm looking for cheapest and from where?
 
I'm getting a 1400VA baby... can't stand it anymore! How long can I expect to do business with a laptop and Wifi ADSL router?
 
jb007za said:
How long can I expect to do business with a laptop and Wifi ADSL router?
Click to expand...

Is that a serious question, or an exclamation of frustration?
Assuming it is serious - almost indefinitely if you can charge the laptop.
A convertor that plugs into your car cigarette lighter is probably enough.

My office door is about 5m from my car, considering just that for emergencies.
 
The other day I didn't notice that my brother had stolen my other multiplug thingie, so I had both my laptop and router plugged into my 600VA UPS. Lasted exactly 30 minutes. I was like "Huh?" *looks under desk* "FSCK!"

Update:

Just ran it with just the router (with wireless ap running) and downloading the whole time - lasted almost two and a half hours.
 
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Don't use a UPS, use a 12V battery!

If you remove the battery from your UPS, and connect that directly to your WRT54 it can last up to 31 hours.

(7800mAh * 12V) / 3W = 31h

Heat and maximum discharge of 70% taken into account, you probably shouldn't run it for more that 18h.

If you're lucky enough to have a 12V DC ADSL modem, you can hook it up to the battery as well. Unfortunately most ADSL modems are 12V AC....

UPS's are huge inefficient beasts wasting a lot of your battery power.....
 
What Tunasashimi said...
Most routers (whole of linksys's WRT54G & WRT300/150N series) run off 12V.DC and use between 500-1000mA... But those don't have DSL modems in them so you'll have to use one which does, or power both the modem and the router if you're planning on using wireless (wireless will use significantly more battery life).
Using an ordinary 7AH 12V battery should keep it running for a long time... just connect one of those batteries to a cable like this http://www.shokaifareast.com/images/Misc_Products/Cable Assy/alligator_dc power_140.JPG which you could actually make using an old transformer cable (http://www.shokaifareast.com/images/Misc_Products/Cable Assy/2.5MM_DC_cable1.JPG) or new one from spar.
If the cable is black, the one with white stripes on it is the positive.
These guys sell the OD Male 2.5mm jack for those who would prefer to just buy one: http://www.communica.co.za/ProductDetails.aspx?DataLink=P_100876146657
 
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Assuming you are not drawing more than the UPS can supply it could run a very long time if you throw out the tiny batteries and hook up larger standby batteries (not car batteries), so the amount of time is dependent on the capacity of the batteries.
Those cheapy UPSs' normally have small low capacity batteries.

I have a 1500VA UPS which came with tiny 12v 7Ah batteries, so I got hold of 2 x 12v 80Ah standby batteries which I've never run down during a 2,5hr power failure running 4 desktop computers, 2 with LCD monitors and 2 with CRT monitors.
I also have a generator with a very clean sine wave output which I feed the UPS with when the generator is been used to power other household equipment.

The way things are going in SA these days (and the foreseeable future) most people will be getting a UPS sooner or later, so when you get one rather opt for the best UPS you can afford.

Bottom line as far as length of time goes depends on the batteries as long as you do not exceed the VA output capacity of the UPS.
 
It's really silly inverting power from 12V.DC to 230V.AC, and then back down to 12V.DC, for an adsl modem... total waste of energy... :confused:
 
fragtion_ said:
It's really silly inverting power from 12V.DC to 230V.AC, and then back down to 12V.DC, for an adsl modem... total waste of energy... :confused:
Click to expand...

I agree if the power is only for the router/modem and you are using a laptop then it would be better to do as you suggested.
 
I wanted to get a 3kVA inverter and a nice battery bank of like 6 deep cycle batts (and a charger of course) and make a nice on-line 'UPS' to power my room during these loadshedding/thundershower times, but sadly lack the necessary funds ;( heh
 
MrH said:
I have a 1500VA UPS which came with tiny 12v 7Ah batteries, so I got hold of 2 x 12v 80Ah standby batteries which I've never run down during a 2,5hr power failure...
Click to expand...

I have a 1KVA UPS that also runs off 2x12V/7Ah batteries. Was thinking about getting another two and putting them in parallel. Should work fine, just a bit scared - the UPS companies all say "No, You cannot do that! Here, buy the 2KVA model" :rolleyes:. They just want my money.

Anyways, where did you get that 80Ah battery? Don't they cost in the range of about R700++? So the UPS was fine with them? Did you connect any fuses of any kind for added protection?
 
ld13 said:
I have a 1KVA UPS that also runs off 2x12V/7Ah batteries. Was thinking about getting another two and putting them in parallel. Should work fine, just a bit scared - the UPS companies all say "No, You cannot do that! Here, buy the 2KVA model" :rolleyes:. They just want my money.
Click to expand...
If you talking about putting the batteries in parrallel then that is fine - but ONLY during the power outage. The moment you have two sets of cells in parallel and the charging circuits come online you'll blow the UPS.

If you talking about putting the AC outputs in parrallel - that is a BAAAAAD idea. If the two inverters are even a couple of milliseconds out of phase they will start pumping power in to each other and canceling each other out. And if they are more out of phase you are going to have a meltdown.

There are some commercial grade UPS's that are designed to run in parallel but they have connections between them to manage the sync of the phase. This is usually only available in the large (2 or 3 kVA and up) UPS's. The UPS companies really do know what they talking about... they not just trying to make money :cool:
 
i dont think 2 extra 7ah batteries will "blow" the UPS? it will probably just put a bit more strain on it [the charger], or take longer to charge the greater battery bank which it PROBABLY wasnt exactly designed to charge.. charger might be rated higher than the stock battery requirements and so might be able to handle more batteries?
 
fragtion_ said:
i dont think 2 extra 7ah batteries will "blow" the UPS?
Click to expand...
Its nothing to do with the capacity of the batteries and everything to do with the fact that they are in parallel.

PS I speak from experience ;)

Edit:
Most of the consumer grade UPS's are designed with very little surplus capacity in order to keep the costs down. The max charging current of the batteries will usually be between 75% and 95% of the capacity of the charging circuit. The moment you put an extra set of cells in parallel you double the charging current which means 150% to 190% of the design current of the charging circuit...... POOOOOF.......
 
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