Dual battery - what have I done wrong??

[digbyj]

Hey guys,
Bought my 05 with a voltage sensitive relay already installed, it's wired to the tub.
Went to my auto elec and showed him setup and asked what was required to hook to battery, simple, cable and terminals and the matching socket.
I've hooked it up.
My dilemma is I then bought a twin 12v cig socket which I connected to the battery and bang, I blew it up. So, what am I missing? I cut the cig plug off to put on battery terminals instead, maybe I connected it the wrong way? The fuse was in the cig plug I removed, hence the bang! Can cig plugs be hooked up either way?
Am I missing something obvious? I'm so close! Please help a dumb ass!
Cheers, Marcus

 

[KraftyPg]

Is you're arse really dumb or are you just pretending?

Cig lighters should be connected the right way, well atleast I have always done it with the marked wire to earth and the unmarked wire to positive. Because of the way they work I'm sure you can't swap the terminals.

Can you see from the plug you cut off which wire is which into the plug and therefore match it to the end of the cable you cut?

 

[digbyj]

The plug has a black and white wire, generally I would presume the black to be neg.
The twin socket however has no distinguishing scars or tattoos, however there is a slight ridge on one of the wires. Not very conclusive really. I've pulled the twin socket apart, the ridged wire goes to the switch and the other to one of the 2 sockets.
Oh and yeah nah my ass/arse is pretty dumb, been about 18 years since I studied electrics at school!

 

[KraftyPg]

Well positive goes to the central part of the socket a negative goes to the outer shell. My guess would be that the wire that goes to 2 points is the earth.

If you cut a cig lighter plug off the end and you can get it apart you should be able to see where each wire connects too and make a decision on which is + and which is - but in cases where it's not black and red it's not always safe to assume that black is negative, it sucks but mass produced after market crap is not always made to a standard.

 

[digbyj]

Yeah cheers Krafty, I reckon the positive goes to the switch, will have to buy a new one and stick a fuse on it.
Am I missing anything else do u reckon? Or if I wire that the right way it's cool just to come straight off the battery?

 

[KraftyPg]

Should be fine, are you sure the one you have is really stuffed, I've hooked heaps of crap up the wrong way and not all them have died and there really is bugger all to go wrong inside a cig lighter connector.

Don't take this as a recommendation (because I've been known to do silly things) but if it was me I'd just get another battery (or disconnect the second one from the car) and wire the socket you have back onto the battery and see if it's really stuffed before buying a new one. A multimeter or even a cig lighter out of the car will tell you if it's working.

For my use it would depend what I was running off the sockets as to whether I'd fuse it, I've got one on mine which is not fused and it works perfectly but then I only use low drain items from it and if I see smoke (which honestly doesn't happen all that often) I disconnect it.

 

[digbyj]

Yeah may not be stuffed, I'll play around with it tomorrow, it's quite simple inside really but there is a circuit board due to having USB outlets i guess. I may be able to rewire it inside.
I'm pretty hit or miss Krafty so I've already tried swapping the terminals but I'll screws few beers tonite and and then try again tomoz!

 

[KraftyPg]

PCB might have a fired component or two so it could well be stuffed and you might be wasting your time trying it, still if you have a few beers and try something it always works better

(oh yeah refer back to previous post I have been known to do silly things so beer and electronic bits may not be a good suggestion for everyone).

 

[Old.Tony]

I recommend - for ALL electrical installations, whether you're experienced or not - the use of either a test lamp or even better a multimeter which, really, is dead easy to use.

Step 1: head to ANY store you like and get a cheap-ass digital multimeter. You should be able to snag one for $10 to $15.

Step 2: Turn the multimeter's dial to "V". Black lead should be in the "Common" ("COM" or "NEG") socket and the red lead should be in "V, POS, mA" socket.

Step 3: Connect the BLACK lead to the body of the car, or the negative battery pole. Hook the bloody thing right there and leave it attached.

Step 4: start touching stuff with the red lead and watch the display. Touch the positive terminal of the battery, it should read 12.6 to 12.8V (somewhere in there for a fully charged battery). Touch the cig lighter outlet. Stab it in your neighbour's hand.

Follow those steps and you will learn one very important thing: you now have a tool that will show you when there is a voltage around. Voltage is good but can destroy stuff if it's the wrong way around.

So you can see what the multimeter reads when something IS the wrong way around, connect the RED lead to the negative (-) on the battery and touch stuff with the BLACK lead. You should see a minus sign on the display, along with the voltages you were getting before.

It's easy as that. It is not rocket science. One lead on one wire, the other lead on the other wire and it'll tell you if there's a voltage there.

Let's get more complex and try finding a break in the wire! Sometimes you need to check if this end of the wire is connected to the other end. It's easy! Move that multimeter to "Ohms" (the Omega symbol). Touch the red and black leads together, the multimeter should read "0.000" - that's because there's a connection. Touch each lead to each side of a fuse - if it doesn't read "0.000" the fuse is blown.

Here endeth the lesson. Hope it wasn't too confusing, but it's something that you could easily do and use that to make sure you don't blow stuff up before you connect it!

Hope it helps!

 

[digbyj]

Haha, yeah I've been waiting for you to reply Tony! You must've been readin
it goin what are these muppets on about! I've been meaning to get a multimeter, great advice and thanks for the step by step, sounds bloody simple.
Might try and borrow s multimeter from work tomorrow until I get one actually.
I'll let you guys know how I go, was hoping to have it up and running for Easter break.
Hey Tony(or Krafty) as per a previous thread, I've got a 6v d cell battery stereo (takes 6 batteries)
if I join the + terminals together and then hook to the battery and same for the - will that work? I've got a 12 to 6v converter but the stereo has no dc point.
Cheers again guys, navara forum does it again!

 

[Old.Tony]

Assuming you've correctly said that it takes 6 batteries - 6 D Cell batteries makes 9V (6 times 1.5 = 9). If your converter has a 9V stage - and importantly, if your converter can supply enough amps to keep the stereo going - then you could do that no problem at all. I've done that myself with one of those 6V (dolphin-type battery) bug zappers.

 

[digbyj]

You are dead right Tony, the bloke i bought it off said it took 4 batteries so I can't get that figure out my head so yes it is 9 volts, as there are 6 batteries. Off to d.smith shortly to get a new twin cig adaptor (and a multimeter!!) so I'll ask them how to wire it, I've got a 9 to 12 v converter.
I like your idea about the bug zapper, I'll see if I can find one...
Thanks for the advice.

 

[digbyj]

Tony/Krafty,
Just wanted to say a big thank you. So far so good I've now got a cig socket hooked up and working! Now I'll attack the stereo, bought a multi meter too. Trucks coming together with the recovery gear/compressor I got for my birthday!
Anyway you guys saved me a trip to an auto elec as I wouldn't of had the balls to try it again otherwise.
Cheers.

 

[KraftyPg]

Glad it's working and that you haven't blown up or something worse.

 

[Old.Tony]

Glad to hear there's progress!

Just on that bug zapper - don't bother, the 6V bug zappers are pieces of crap.

I bought a solar powered (runs off a single AA battery for an entire night) bug zapper from Bunnings and it beats the daylights out of the dolphin-battery-powered one.

If you want one - don't bother with the crappy little one that looks like a solar path light. Get the large black one that looks like an old-fashioned square lantern.