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Wiring a 12v socket to a deep cycle battery?

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5 replies to this topic

#1 M Cherch

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Posted 06 August 2014 - 08:58 AM

I recently built my own power tank out of a 125 ah deep cycle marine battery. I used these schematics:


It works like a charm powering my telescope, but I also need a regular 12v socket to charge my laptop / camera. I tried using a 50watt power inverter, plugged it into one of the ciggarette lighter outlets, worked for literally 5 seconds, and then stopped working. Tried it over and over again and the same thing kept happening. I would really appreciate some advice on how I would go about making a regular socket happen... id appreciate it! Or at least point me in the correct location.. thanx again!


#2 BarryBrown


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Posted 06 August 2014 - 09:18 AM

50 watts may not be enough to power/charge the laptop. Try an inverter of at least 100 watts. 

#3 Tom McDonald

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Posted 06 August 2014 - 01:25 PM

In my experiences using a power inverter, I always plugged the inverter into a vehicle with the engine running. Otherwise the inverter as well as whatever was plugged into it would drain the battery quickly.

#4 richard7


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Posted 06 August 2014 - 02:38 PM

You can consider that all laptop chargers draw at least 100 watts for even the smallest ones.

There should be a label somewhere on the charger listing how much the input voltage and current are. Multiply the two together to get your approximate wattage.

Try to get an inverter with at least twice the average rating (not the peak rating), maybe more if you'll have any other items to plug in later.

#5 Geo.



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Posted 06 August 2014 - 05:13 PM

Why not set up your power supply to power the laptop and camera? These sell for under $10 on eBay.


And these for under $5:


#6 n1wvet


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Posted 07 August 2014 - 12:11 AM

Agree 50 watts is not enough for a laptop.  Also are you sure your laptop takes 12 volts?  My dell runs on 19.5 volts at about 5 amps.  Granted it's an older model.  Check the power requirements and votage requirements of you devices before building anything.  They do make 12 volt converters to power higher voltage devices.

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