Hi i have one of these chargers and i also bought the cigarette lighter adaptor so that i could hopefully charge my battery through the cigarette lighter (power socket). But im unsure as to how i should wire the cigarette lighter in, should i power it straight from the battery via a fuse and take ground to chassis or to battery. Any help much appriciated Greg

I would take it from a fuse at least you have some protection on your wiring. You can either take it from a permanent live ie accessory or switched so it will only power up when the ignition is on

Hi, I would connect it directly to the battery with a reasonable fuse, but it would not make any real difference if you went to chassis or direct with the earth. Just ensure that the earth is a good one..

The thing to be aware of is that the lighter socket will be live all of the time. It may be an idea to put an isolation switch in it so that 'someone' cannot plug anything in when you are not looking and flatten the battery.... or worse.

My thoughts,
You dont want a live from the battery going anywhere, What goes in the battery can also come out!
So a Fuse as close to the bat as possible (within 6" of wire would be fine) to stop any shorts when its not in use. The charger will have its own fuse to protect it. Also if you have a cigarette lighter you can use it for other things if fitted in a suitable location. Its a slow charger so no big amp fuses required.
Earth should go straight to chassiss. As short as neatly allows.

As above isolation may need to be considered but useless if you want to keep it 'topped up' in the garage like these chargers are best for.

Hope this helps and that others agree!!

[Edited on 3/2/10 by bi22le]

I have a cigarette lighter socket on my dash - mine has a hinged lid on it, as I don't smoke - they're usually rated at 10A so I put a 10A fuse just behind it. It's wired to the permanently live circuit and my maintenance charger is always plugged in there when the car's not in use. A crossflow engine needs a fully charged battery on cold mornings!

[Edited on 3/2/10 by David Jenkins]

i use the optimate for my motorbikes and jetskis over the winter and its great just clip it to the battery.
or buy a lead for you fag liter on ebay

http://cgi.ebay.co.uk/OPTIMATE-ACCUMATE-BATTERY-CAR-LIGHTER-SOCKET-LEAD-TM72_W0QQitemZ350312717313QQcmdZViewItemQQptZUK_Motorcycle_Parts?hash=item5190 43dc01

[Edited on 4/2/10 by thunderace]

I ran a wire to straight from the battery via a 15A fuse to a relay. The relay is switched by a feed from the main loom. Then it goes to the +ve supply of the 12v socket. Negative goes to the chassis.

Advantage of doing it this way is that you can pull 15A and it's not going via the main loom but then the supply to the socket isn't on when the ignition is off so you don't get the battery running down....