I doubt an overvoltage of a couple volts would cause an issue. But a bad connection that causes a voltage drop as current increases certainly would. I think a bad connection is the likely problem.
How to charge a tablet from dc power supply?
- Thread starter Gueyog8a7
- Start date
Maybe this could be it since the connector I used was one that was in the garage electrical box and probably over 30 years old. I guess worth buying a new one to try that.
theoldwizard1
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- Jul 17, 2020
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Because it is safe, easy and it works !
Also very expensive compared to other options I guess.
I would sooner buy another tablet that could charge by usb out of the box. Or a raspberry pi which was my original plan but since my mum already had this spare tablet I am trying to figure if it will work for me first.
Would the cigarette lighter option also have the same issues? I don't want to use the van's port to drain the starter battery, which I already have issues with if I do not drive for a while, so I am guessing I can buy a port to connect to the leisure battery and also the adapter for the tablet but will the same lack of charge issue likely be the case?
theoldwizard1
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- Jul 17, 2020
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If the cigarette lighter is on the dash, it is getting probably getting power from the starting battery. Depending on the vehicle, some cigarette lighter outlet may or MAY NOT be power when the vehicle is OFF.
So I bought a new connector and tried and still the same thing.
I even tried charging with the first one overnight and by morning nothing perceptible was added,
Something else interesting to note though. There is a second 'wall wort' not made specifically for the device, that is BESIDES, the one I already posted, for clarity. We tried to use it weeks ago and thought it didn't charge however tried again the other night overnight and it charged it but it seems much slower than the intended charger. This second one has a screw turning on the adaptor to alter voltage up to 12v maximum and that was what it was on.
This is what made me think that trying in the van again would work if I waited longer since this second one worked at a slower rate and seemed to fully charge over night on the mains supply in the house. Alas charging from the battery still did nothing that I could see.
So my only options now are cigarette, dc-ac-dc inverter or new tablet that will charge via usb?
What is the liklihood the cigarette lighter way would be any different? I also don't want to plug into my existing cig port since it is connected to the starter batt which would mean buying a port just for this but if it is still 12v why would it be any different than the initially problem of being underpowered?
I even tried charging with the first one overnight and by morning nothing perceptible was added,
Something else interesting to note though. There is a second 'wall wort' not made specifically for the device, that is BESIDES, the one I already posted, for clarity. We tried to use it weeks ago and thought it didn't charge however tried again the other night overnight and it charged it but it seems much slower than the intended charger. This second one has a screw turning on the adaptor to alter voltage up to 12v maximum and that was what it was on.
This is what made me think that trying in the van again would work if I waited longer since this second one worked at a slower rate and seemed to fully charge over night on the mains supply in the house. Alas charging from the battery still did nothing that I could see.
So my only options now are cigarette, dc-ac-dc inverter or new tablet that will charge via usb?
What is the liklihood the cigarette lighter way would be any different? I also don't want to plug into my existing cig port since it is connected to the starter batt which would mean buying a port just for this but if it is still 12v why would it be any different than the initially problem of being underpowered?
Well there is no question it is because I installed the leisure battery electronics myself and no other power but the stock electrics in the van before which would all be via the starter. Don't want to use that for this as it would be in use constantly.
I just found this. Would this likely work or end up being the same as the original issue of being underpowered? I don't see what will change if it will still step down to 12v?
Andrewr05
[Replicant 42069]
Honestly, if even your stock charger isn't charging the device (unless I'm misunderstanding you) then I think there is a problem with the device itself and not the charger.
You are.
The stock charger works flawlessly.
There is a second charger, which is not the standard one, which I tried because it says 12v which I thought might be the same as charging from my leisure battery to compare it. It charges from the mains with that one but extremely slowly.
Not charging at all that I noticed when connecting direct to battery.
That was it. Finally got it going after a couple of more suggestions along this line.
Was able to find a step down convert for only just under 2 pounds which is adjustable. See here.
Working fantastically now. Really pleased to have plugged away and figured it out rather than acquiescing to one of the simpler solutions. 12voltplanet were advising a victron converter which would have costs 60+ quid.
Now I would also like to charge my phone. This linked device states 5a but the wall charger for the phone only wants 0.55. A little reading suggested that the amperage of the charger is irrelevant due to ohm's law and so it would be fine to use another one for this since the charge will only draw what it wants and won't risk any damage to the charger.
Just want to double check that is right so then I can go ahead and get another for phone charging from the battery. I will snip the wall plug wire to use the connector since it is an old phone with a non standard connection and rig it up to converter and battery like I did so with the tablet above provided I get the all clear the 5a will still be fine, which my cursory look online revealed it would be.
0truck0
New Member
The reason I use an inverter in my truck is because modern vehicles have a lot of electronics and circuit boards and computers that run everything from motor to transmission to you-name-it. Sometimes when you plug in devices it can cause interference with the vehicle computers. Yes, this has happened and the fix was to unplug the toys. The real solution is to use an inverter!
The inverter separates the vehicle electronics from the devices you are charging, no more interference.
The other benefit, as mentioned, is you get a cleaner power source, especially if you use a pure sine wave inverter vs a modified one.
For chargers and bricks you can use a modified sine wave inverter, but the pure are so cheap that I would never ever again use a modified sine wave. Not everything can be plugged into a modified sine wave, these things will fry quickly.
A 300 watt inverter is plenty for what you are doing, is small too, but use 8 gauge wire and connect as directly to the battery as possible, 10g ok, but if you have 8 is good. I plug into a DC outlet and that powers 5 usb outlets, and run all my stuff off those outlets. I have not yet run the direct 8 gauge wire....
Yes, seems nonsense to go from DC to AC back to DC but this truly is the best solution.
I also charge my 18 volt tool batteries off this inverter, charger plugs into 120 outlets, it is the only way I have charged them for the past year. Is nice when you use tools for work and just charge them while you drive to next job; batteries never leave the truck.
A pure sine wave inverter, even the cheap ones, have very clean waves, far superior to what comes off the power lines.
If you have sensitive devices then using an inverter is just smart.
I have the exact same 300 watt inverter in my camper too. It runs a small TV and charge laptop, never needed it for anything else. The TV is 18 volts and I want to get a step-up transformer but just easier to use the inverter. Always keep an eye out for 12 volt tvs. TVs will plug into 120 wall outlet, but all run on DC power, the change happens inside the TV, but you can open the tv and bypass the transformer if you have the right voltage. 12v tv will run on 13.5 easy enough.
The inverter separates the vehicle electronics from the devices you are charging, no more interference.
The other benefit, as mentioned, is you get a cleaner power source, especially if you use a pure sine wave inverter vs a modified one.
For chargers and bricks you can use a modified sine wave inverter, but the pure are so cheap that I would never ever again use a modified sine wave. Not everything can be plugged into a modified sine wave, these things will fry quickly.
A 300 watt inverter is plenty for what you are doing, is small too, but use 8 gauge wire and connect as directly to the battery as possible, 10g ok, but if you have 8 is good. I plug into a DC outlet and that powers 5 usb outlets, and run all my stuff off those outlets. I have not yet run the direct 8 gauge wire....
Yes, seems nonsense to go from DC to AC back to DC but this truly is the best solution.
I also charge my 18 volt tool batteries off this inverter, charger plugs into 120 outlets, it is the only way I have charged them for the past year. Is nice when you use tools for work and just charge them while you drive to next job; batteries never leave the truck.
A pure sine wave inverter, even the cheap ones, have very clean waves, far superior to what comes off the power lines.
If you have sensitive devices then using an inverter is just smart.
I have the exact same 300 watt inverter in my camper too. It runs a small TV and charge laptop, never needed it for anything else. The TV is 18 volts and I want to get a step-up transformer but just easier to use the inverter. Always keep an eye out for 12 volt tvs. TVs will plug into 120 wall outlet, but all run on DC power, the change happens inside the TV, but you can open the tv and bypass the transformer if you have the right voltage. 12v tv will run on 13.5 easy enough.
Mason Parsons
New Member
You can charge your tablet from a DC power supply in your van by using a USB connection. Since you have two USB ports, you can connect the tablet directly to one of them. Make sure to use a USB cable that is compatible with your tablet. If you prefer to charge from a blade fuse block, you'll need to rig a setup that connects the fuse block to the tablet's charging port.
You may need to use a fuse tap and some additional wiring to make this connection. Remember to check the power requirements of your tablet and ensure that the DC power supply can provide enough power to charge it safely.
You may need to use a fuse tap and some additional wiring to make this connection. Remember to check the power requirements of your tablet and ensure that the DC power supply can provide enough power to charge it safely.
