View Full Version : Tablet powered direct from Battery
rocket rod
25th October 2016, 10:22 PM
Has anyone connected their tablet directly to a 2nd battery? I read that USB is based on 5V and of course the car is 12v but I would like to wire it up to my dual battery system. I have a fuse box located in the spare space under the bonnet in front of the driver's seat.
The alternative is to wire the cig plugs on the dash to the dual bat system. Don't know which is the easiest of the two.
Blknight.aus
25th October 2016, 11:49 PM
you cant do it directly as most tablets are 5V charge. (there are or were a few that were 12V but I dont think they'd like the 14.4 you can get from an auto system)
I would do it by putting in a pair of dual 2A usb panel mount sockets and then plumbing them onto your aux battery via a small switch and a fuse (they draw a few mA when not in use and can get warmish.)
then you can plug in anything that has a USB cable to charge it. Word of warning some apple products may not switch over to fast charge on those sockets so a genuine apple cig socket adaptor is the go there.
cjc_td5
26th October 2016, 03:13 PM
Has anyone connected their tablet directly to a 2nd battery? I read that USB is based on 5V and of course the car is 12v but I would like to wire it up to my dual battery system. I have a fuse box located in the spare space under the bonnet in front of the driver's seat.
The alternative is to wire the cig plugs on the dash to the dual bat system. Don't know which is the easiest of the two.
I have one of the cig plug on the console wired to the 2nd battery, so it is permanently powered. I have a twin USB charger in this to charge phone/tablet etc. The other cig plug is on the std circuit so only alive when the vehicle is powered up. Best of both worlds....
rocket rod
26th October 2016, 05:40 PM
I have one of the cig plug on the console wired to the 2nd battery, so it is permanently powered. I have a twin USB charger in this to charge phone/tablet etc. The other cig plug is on the std circuit so only alive when the vehicle is powered up. Best of both worlds....
Thanks for that Chris. How did you tap into the wiring to the cig lighter. Did you take the console apart? Something I'm loath to do.
Blknight.aus
26th October 2016, 06:47 PM
Let me know if you want a hand wiring in.
Im currently local(ish)
DiscoMick
26th October 2016, 07:39 PM
Your dash plug is already connected to the dual battery system, but of course it won't work when the ignition is off.
I have a Narva double plug connected through a 10A circuit breaker to the second battery under the rear drawers. One plug has the rear fridge plugged into it. The other one has a double USB socket plugged into the cigarette plug. This means the grandkids in the back seats can plug their phones or ipads/tablets in and charge them. This plug is always on.
In the front I have a twin Narva USB plug connected to the starting battery through a 10A circuit breaker. This plug is always on.
I also have a double USB plugged into the dash cigarette lighter. This plug only works with the ignition.
The front plugs power the reversing camera and charge our two phones.
The starting and second batteries are linked through a Traxide DBC and a heavy connection with twin 60A fuses.
Power needs vary, of course. The fridge and the reversing camera only operate when needed. The phones are only plugged in sometimes. If only one thing is working I think it can draw up to about 4.5A. If there are 2 it is shared.
It all seems to work fine.
I'm about to fit an 80A solar panel to the roof rack and run it through a 10A regulator to charge the starting battery.
Sent from my GT-P5210 using AULRO mobile app
cjc_td5
26th October 2016, 08:21 PM
Thanks for that Chris. How did you tap into the wiring to the cig lighter. Did you take the console apart? Something I'm loath to do.
Centre console out job. It's not that hard. I posted a PDF of the TOPIx instructions on here not that long ago. The cig lighter has std blade type prongs so it is easy to run a 2 core wire to, directly back to the 2nd battery (via a fuse of course).
Powered by vBulletin® Version 4.2.4 Copyright © 2025 vBulletin Solutions, Inc. All rights reserved.