12v socket polarity

bongolow · Post by **bongolow** » Wed Sep 26, 2007 6:29 pm

What's the usual polarity of the 12v square type sockets, as per.....

It's marked N & L but the L is negative - I would have thought it should be the other way round.

I've never actually used this socket until today but I suspect that it's wired the wrong way round - I've just bought a car charger for my MP3 player and it went up in smoke (literally!) when I plugged it in, so I think there's a clue there...

pippin · Post by **pippin** » Wed Sep 26, 2007 6:35 pm

I suspect that if you undo the two bolts that you will then be able to swap over the connectors to un-reverse (?!) the polarity.

bongolow · Post by **bongolow** » Wed Sep 26, 2007 6:41 pm

I suspect that if you undo the two bolts that you will then be able to swap over the connectors to un-reverse (?!) the polarity.

Yes but I just wanted to check if there's a 'standard' for the polarity of these sockets. I was using an adaptor - square socket to car type socket - and it could be this that's wired the wrong way.

Sorry, I should have explained better in the first post.

Manny · Post by **Manny** » Wed Sep 26, 2007 10:34 pm

I use those sockets in my bongo as well as I think they make better contact than the cig sockets. The only problem is all the equipment with standard cig plugs have to have the plugs changed to be connected. I believe the L and N stand for live and neutral. The L should be connected to the 12 volts and the N to chassis or 0 volts. I also had them in a previous motorhome and that was the way they were connected.

Manny

bongolow · Post by **bongolow** » Thu Sep 27, 2007 1:09 am

Thanks for the confirmation Manny, I was fairly certain it's wired wrongly.

I managed to prise the adaptor apart, with a little persuasion - it's blown the converter chip (note the split!) and fried a resistor. It's also got a fuse in it - fat lot of good that did!. The number on the chip is just visible and they have them at RS for just over a quid so I'll bung a new one in and see if it works. Not much else in the thing so it should do - worth a go anyway, before I shell out another nine quid on a new one.

pippin · Post by **pippin** » Thu Sep 27, 2007 9:36 am

I would change the (any) electrolytics as well.

Manny · Post by **Manny** » Thu Sep 27, 2007 9:40 am

Bongolow it looks from the photo that resistor R1 has also been cooked.
I would try and change that as well, although its going to be a guess at what its resistance might be as the colours in the code have been burnt to black except for the first number, which is coded brown for 1.

Manny

RobinS · Post by **RobinS** » Thu Sep 27, 2007 11:08 am

Bongolow - as a matter if interest, was your socket fitted by a well known convertor with Manchester in thier name? Ours came from them, and the socket was wired the wrong way round in ours as well!

Robin

bongolow · Post by **bongolow** » Thu Sep 27, 2007 11:34 am

Pippin - yes, I'll change the electrolytic (there's only one) and there's a zener diode as well which I'll change.

Manny - I'll check the resistor. At the moment it's reading a dead short across it but I haven't removed the IC yet. According to the data sheet (isn't the 'net wonderful) it's the resistor that adjusts the output voltage so I'll have to see what voltage I'm getting and replace accordingly.

RobinS - yes it was! I'll drop him an email.

james1508 · Post by **james1508** » Thu Sep 27, 2007 10:37 pm

Hello
mine was too wired up wrong and the new tv i had just purchased never worked again. I used a meter to confirm this and changed them around and made sure i insulated it again so not to short circuit the live against the van. I dont know why this is but someone somewhere isnt very good at electrics. I use a 2 pin converter to change into a cig lighter.

james

12v socket polarity

12v socket polarity

12 v socket