Reversing camera install wiring question

[AndyS95]

Hi all

Just thinking about an upcoming install of a reversing camera..

Most likely will wire it in to the 'beep box' in the drivers footwell. I haven't looked at the connection yet but when I do is the best option to stick a wire into the junction box and feed it out to the camera or should i splice into the wire before it goes into the junction box? (Or something else altogether!?)

I assume I then just earth the camera at the other end to somewhere appropriate?

Another thought occurred to me - I think from memory I have the 7 pin caravan type towbar connector, if I put the live wire into the reverse hole would that work?

cheers, Andy

[g8dhe]

Its more normal to pickup the power from the reversing light than to try to run power all the way back to the rear door from the Sound Warning System module, the signal is the same one after all! The other option is to power the camera all the time via the Ignition switch and choose to switch the display on when required - this means you can watch the idiot who runs into the back of you when your already parked up! This is what I do.

[dave_aber]

I powered my camera from the reversing lamp feed in teh rear cluster, and used the "infernal beeping box" signal to feed the trigger wire to the head unit to switch it into camera mode.

I did consider just feeding it permanently and using a switch though, as sometimes it would be handy to have it on without actually being in reverse.

[AndyS95]

Thanks guys, yeah I hadn't thought about a switched permanent live option, was too transfixed with the magic of it coming on and overriding the screen when reverse is selected..

But thinking about it, a switch makes sense - just flick it when required..

So (a stupid question i know) could you advise the best option / process for getting a live feed off the ignition please?

cheers, Andy

[dave_aber]

There's not much down the back end that is only switched on with the ignition - except the rear faglighter socket in the side panel. Beware though - the wiring to this is notoriously weedy and can't stand much current draw. Mind you, a rev. camera is probably not drawing more than about 0.25A - there's plenty which you could just plug in and draw more than that!

You mentioned a towbar wiring - do you have the grey caravan socket too - IIRC that has a switched live in it? <- Edit - It's a perm. 12v, unless you have a switching relay wired in ( a good idea) to make it only live with ign.

[AndyS95]

Thanks Dave, yeah I think I have the caravan one, i keep forgetting to double check when I am home though.. I put a new cig lighter in the back and it so far copes with the 19" TV but I should get round to upgrading the wire I guess..

If I am going to have a selecting switch in the dash though wouldn't it make more sense to get the power feed from the front?

Cheers, Andy

eta my rear cig ligher is off the LB as well..

Sorry another eta: What rated wire should I use (for the reverse camera and to replace the rear cig lighter wire) and would a piggy back fuse adapter be a good bet for the live feed and what fuse should I use there?

Sorry for all the questions just adding them as I think of them! Thanks in advance

[dave_aber]

Just been checking a few online - the wireless ones which obviously have a camera and a transmitter to power draw 100mA, a wired camera will draw around 40mA.

So, if you are running a 12v feed from the front of the vehicle I'd personally use a circuit run in 0.65mm² cable (about as small as you can get) which is rated at 5.75A. I'd fuse this at the source of supply end - Pretty much any fuse under 5.75A would be suitable, so for sake of argument 3A. 1A would also be fine. As long as it's less than the rating of the cable and more than the load of the device at the end you will be fine. On such a low current application, you won't suffer much in the way of voltage drop running a long cable.

For the rear lighter socket, let's assume a max. continuous load of 10A. This seems to be the accepted wisdom on the good old internet - although I was really looking for a safety rating for the actual socket, so we don't melt it! Seems that these are sometimes fused @ 15A, so let's say 10A in use to be safe.

2.0mm² is cable the first size above 10A, and is rated at 17.5A, so plenty of safety margin. Your call on fuses - below 17.5A so that the cable is protected, and above the running current of whatever we plug in - 10A or 15A are the options for standard fuses.

Cable and fuses here : http://www.autoelectricsupplies.co.uk/home

[AndyS95]

Thanks so much for taking the time to check the info out and reply Dave - really appreciate it.

I'll report back once I get round to doing it..

cheers, Andy