Based on the cig adapter, then 15A. But you could go 10A as discussed. (And maybe the 15A is to limit for the cig plug/socket which are normally rated at a max of 15A, though few actually handle that!)
The GM wiring for 10A should be ok, but many would run separate wiring for stuff like this, though a laptop isn't that critical. IE, it runs off its battery rather than being dependent on a good supply - not that intermittent or bad contacts would be good for it, or the converter. (If it were a cig socket, I'd feel the heat.) Many of us run our own wiring direct from the battery for PCs, audio, etc. (I do, for a normal HU and a spare cranking battery; both have dedicated + & - from the main battery. I have no PC.)
One fuse is fine. EG - if it were f.ex 50A wiring from the battery thru a 30A fuse thru a 30A relay to the dc converter with its 10A or 15A fuse, then the converters fuse could be moved to the battery instead. IE - battery with 10A or 15A fuse even though wiring and relay is 50A & 30A etc. The fuse still blows (in theory LOL) before the wire or relay melts, and it still protects the converter. (That protection is against shorts etc - not against failure.)
I'm not sure what you mean by the GM circuit supplying to activate & power the relay. In my setup, that circuit might activate the relay which switches the (fused) battery power. But if it both activates & powers, the there is no need for the relay (unless later you wanted to add some sort of off control, but then why not get the heavy power from the battery so you could activate with the GM circuit (= ACC?, hence off when cranking?), or a manual switch or a voltage switch etc?)
Glad you understood my crap. It was late last night - not that that necessarily changes anything.
But now is early morning, pre-coffee etc. And I'm up early to start a new job. Holy cow - it's still dark outside!
What I meant was I'll be taking the 12v switched signal (ACC) to activate relay and use the 10A IP2 (Always Hot) fused circuit which used to be for the factory stereo to power the DC-DC converter. Very much so like this:
I however, can easily run a new fused wire from the battery to provide the actual power instead of using the factory IP2 fuse (Battery is under rear seat). I would prefer to not have a bunch of terminals and wires going to the accessory extension on my battery post. I am contemplating getting an auxiliary fuse block. As I have two amplifiers and three separate circuits to my LED tail lights already tied to the battery. Just makes for hassle to remove battery if ever need be. It may also be time for a "tank" circuit with an aux battery.
BTW, oldspark, does this project look familiar? I believe we have crossed virtual paths before haha!:twitch:
Good - you did mean the right thing.
Stick with your orig idea - change to direct battery connection only if needed etc.
(BTW - the LEDs should be low power so off one feed should be ok.)
And yes, I remember that blue thing... that was a LED conversion wasn't it? (I'd never recognise a description, but the pic yeah... simple minded me you know lol!)
I use this one (150W DC-DC Boost Converter 10-32V to 12-35V 6A Step Up Voltage Charger Power) that I bought on ebay. The output is adjustable. I run mine at 19vdc and it works fine. If the pc is on, it is not affected at all by cranking.
Originally Posted by sall