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battery backup for modem 2

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young707

young707

Electrical
Aug 11, 2014
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I am seeking battery backup for modem (DSL & cable) for 12VDC 3Amp.

Is there readily available consumer grade 12VDC battery systems so that we can power our modem and recharge our cell phones/tablets when power goes our?

Otherwise, what is the circuit available to regulate & current limiting. Also splite out lower voltages for USB charging outputs.

I prefer using commercially available rechargable 12VDC lead acid batteries.
 
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Why do you expect to get something for nothing? You want a ready made solution by spending what a $20 battery costs...

At first I though you were meaning a large flooded lead-acid battery and since then you seem to be under-estimating your power requirements with the link to that cute little SLA battery. It will power just your 12V requirements for 70 minutes assuming you only discharge it to 50% capacity. Add a 2.1A USB device charging and you won't make it to 55 minutes. If the outage is significant then you'd have a vehicle running continuously charging batteries so you might as well just take power directly from it.

 
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I do not recommend to run car to power DSL/Cable modem / router with wifi and ethernet.

this car jumper is 8000 mAh / 400A for $32

this mini DC gets 15600 mAh for $45.39
It would be nice I can convert this to run off 12V rechargable lead acid battery

This is nearly what would work. Need USB charge output ports. Also need circuit to charge the battery circuit by car.
 
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There's possibility that the SK616 is using 18650 Li-ion batteries, which is actually a plus, in my mind, since those batteries are used in lots of things, like flashlights and headlamps:
SK616_rrh2vk.gif


TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
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You mean you don't want to run the car to power the equipment?

The jumper pack Keith linked says 20Wh in the specifications. You'd get <30 minutes of run time powering a 12V at 3A load with that rating. I'm not sure where the 8Ah rating because 96Wh isn't close to 20Wh. Kind of makes one skeptical of the ratings for any similar Li-ion battery device.

You do know that the smaller SLA batteries can't just be connected in parallel with a car battery and then run the car to charge them? At least not without damaging them.
 
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SLA = Sealed Lead Acid (battery).

During extended power outages, unplug the Ukrainian eBay gadget from the wall, and then plug it into a 12Vdc-to-120Vac inverter that is in turn connected to your other source of nominal 12 volts.

But a car idling in driveway for hours or days on end? Not a great idea. You might be surprised how much gasoline an idling car uses. At some point, a very small generator or a solar panel system starts to make sense.

One of the killer features that *could* be offered by future electric cars would be to provide emergency power back to the house during shorter power outages. It would need to be fully integrated, and intelligently controlled.

 
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VE1BLL said:
One of the killer features that *could* be offered by future electric cars would be to provide emergency power back to the house during shorter power outages. It would need to be fully integrated, and intelligently controlled.
Click to expand...
I thought Tesla had already mentioned something to that effect when they were first coming to market...

Dan - Owner
URL]
 
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