I’ve just bought a little screen for a reversing camera for a car. It’s meant to wire into the car electrics but i want to use it externally. So what kind of amapage should i be looking for on a 12v power supply?

Unclear what you mean. Externally to what? What is the 12V supply?

12v power supply is a plug-in transformer, like thekind of thing used to charge many electronic devices.

Externally means external to the car, like in my house.

Typically around 5 watts so less than 0.5 amp, but a 1 amp setup would probably do.

No motors and just electronics, very little I’d think. Does it have a label stating the wattage? If so just use Ohms Law to find amps.

Oh right.. there should be a sticker on the back giving wattage? Then divide by 12 to get the current requirements.

A car lighter socket can only supply 10A so it’ll be less than that. A lot less, most likely!

Ok, i have a 12v 1A transformer from an old modem, so long it doesn’t kill my screen.

No, no wattage,it came from hong kong via the internet

How does the screen plug in? If it’s a thing that goes into the cigarette lighter, there could be a voltage regulator in there. You positive that the screen’s 12V?

No it’s a thing which wires up rather than plugs in, yeah it is 12v

12v 1amp will likely be enough unless its some aweful cheap thing (in which case it will have a 2amp electric heater inside it lol).

Freely available on ebay. Depends what connector you need, but I generally just buy the cheapest thing going and stick my own connectors on it etc.

BTW average car battery is 40-60aH, but electronic things only draw what they need, its the correct voltage you have to supply them with.

Brickman what is that funny little ad that comes up with your text?

Anyway, plugged it in with a 1A 12v transformer and nothing happened. There is a 2A fuse in lead to the screen, but surely that is just surge protection.

When you say transformer, do you mean a complete power pack black box thing, or just a transformer on its own?

Surely he means one of these transformers..

Anyway, plugged it in with a 1A 12v transformer and nothing happened.

are you feeding it some video?

Just a power supply like you used to get as a phone charger

No, not feeding it video yet, wanted to see if it would power up

No, not feeding it video yet, wanted to see if it would power up

I take it there’s some sort of power indicator then?

There’s plenty of monitors that wont visibly power up without a video source being present

If its a reversing camera, wouldn’t it only operate when you are in reverse? Or as above, no video input, no power on.

I’d expect the backlight to come on though.

I’d expect the backlight to come on though.

not on all, the power is triggered by the video

erm no, no power indicator

ok so it works with a camera feed

ta

Ok, just in case people happened to be interested. I just got a Raspberry Pi and was looking to see if i could run it on a mini screen. I can!

Hooray!

Can you read the text though?

Some of the time, but not all of the time

SamCooke – Member
Some of the time, but not all of the time
POSTED 42 MINUTES AGO # REPORT-POST

😆

Edit: Respect for having a bash with the Pi – I need to do something with the one I bought.