Wassup everyone.. working on my car pc project and had a quick ? about wiring. i plan to install an addon 3port cig adapter (it has a power cable that plugs into a single cig adapter) but dont' want to plug it into a cig adapter. i want to wire it directly to my car battery and want to know if i'm going about this correctly. run power cable from battery to 3port, put inline fuse on power cable. Connect power cable to + wire of cig adapter, ground - wire to chassis, boom.. good to go.. is that fair to say? also, any suggestions for the fuse size? thanks seamonkey420
Hi seamonkey, Your wiring sounds right. Car lighter fuse is usually 10Amp. Since the 3 hole adapter is made to go into that, I wouldn't go higher than 10 amp. The wiring on the adapter may not handle more. The adapter may have the max amp listed on it somewhere. Jerry
thank you for the confirmation!! much appreciated.. decided to do this: wire my lcd to headunit's ignition power and ground (with inline fuse) to my lcd's dc12volt car adapter. i believe car adapter has built in fuse but just to be on the safe side.. decided to just disconnect my factory cigarette lighter and run it to the 3port (worried about battery getting drained by pc and fire!! hehe, still a total newb at wiring/fuses/power stuff). and then run my car laptop dc adapter to one of the cigarette ports. gonna throw an inline fuse between the connection from the factory cig adapter connections to 3 port (again, not sure about if its fused or not, being on the safe side) and using a 10amp fuse as suggested.. just looked at my owners manual and noticed that my stereo and my cig lighter share same fuse, do i have to worry about not having enough power if i wire things like above? i do have a nice headunit, pioneer premiere mp3 deck and 400 watt amp.. (amp run directly to battery of course).. if you see anything that might be bad, let me know. .hehhe.. i appreciate the help! i'll post pics once i'm done..
Hi seamonkey The effect on the headunit will depend on the current draw of the accessories you have added. Modern headunits draw their power through the constant feed - that is how the new high powered units work. In the old days (5 years ago) all the power was through the ignition. I would run a 10 g power wire fused with a 30 amp fuse at the battery. I would connect this wire to a 30/40 amp Bosh relay - pin 87. Pin 30 of the relay would go to a 25 amp fuse in a 10g fuseholder connected to the 3 port lighter. The ground of the lighter would connect to frame with a 10g ground wire. Pin 86 of the relay would go the the ignition wire at the headunit. and pin 85 would go to ground. With this setup the key would have to be in the ignition powering the radio thus no dead batteries when the car is shut off. The 10g wire is to provide up to 30 amps of current needed to run the accessories plugged into the lighter sockets. To calculate the size of fuse check the fuses of each of the items plugged into the lighter - add them together and you will have a rough estimate of the current needed to power the circuit and therefore the fuse size. I hope this helps
