[Keith L]

Do any of you Yeti techno heads out there know where there is an ignition fed pick up that I can tap into in oraroundthe rear boot area that will allow me to connect a fridge to without using the standard 12v. socket outlet? this standard socket has the potential to flatten the battery over long periods of none driving use.

 

[Tech-Yeti]

If you fit another socket next to your old one and connect it via a 14v relay to the existing one you will have 1 that works at all times and 1 that works only when the engine is running.Relays are very easy to install, google images "14v relay diagram" wire it the same as a spotlamp.
If you prefer, it wouldn't cost much for an auto elec tech to do it.

 

[Keith L]

Many thanks for the feed back; however, I would still need the 12v ign feed to power the relay, surely?

 

[Tech-Yeti]

Many thanks for the feed back; however, I would still need the 12v ign feed to power the relay, surely?

1. No, splice into the 12v supply to the existing rear socket behind the panel using both cores of a 2 core 10 amp cable.
2. Split the other end of the cable and connect to the relay terminals 86 & 30.
3. Connect the relay terminal 85 to an earth using 1 core 10 amp cable.
4. Connect the relay terminal 87 to the extra sockets power supply terminal, using 1 core 10 amp cable with a 10 amp inline fuse on the cable.
5. Connect the extra sockets earth terminal to an earth.
NOTE: Forget any other terminals that might be on the relay, but it must be a 14v not a 12v relay.
Example of relay:http://www.ebay.co.uk/itm/Low-Current-Switching-Relay-HG4185A-012-1H-14V-DC-40A-/150944238093?pt=LH_DefaultDomain_3&hash=item2324fa4a0d

This will leave your existing socket working as normal, but when you start the engine and the alternator kicks in the voltage will increase to 14.2v and more. This will switch on the relay, which in turn will make the extra socket live.
When you turn off the engine the voltage will return to approx 12v, the relay will switch off and the extra socket will be dead.

Hope this makes things a bit clearer

 

[Tech-Yeti]

Just knocked you up a quick diagram, hope this helps

 

[The Hood]

I wasn't thinking of adding such an outlet but I am now, what a brilliant idea, and no messing about with lengthy cables

 

[Keith L]

Never thought of using a relay this way before. Many thanks for your invaluable help. Buy you a beer at the next Yeti meeting!

 

[Llanigraham]

A little point.

The designation "14volt" on that relay does not mean it only works when the voltage gets to that level, but means that is the maximum voltage it is designed to pass.
Those exact same relays are used to power auxillary lights, horns etc.

And your diagram shows there is power to both the switching and power sides of the relay

http://www.google.co.uk/imgres?imgurl=http://www.texasindustrialelectric.com/images/hella_Relay_drawing_SPDT.gif&imgrefurl=http://www.texasindustrialelectric.com/relays_Hella_007794321.asp&h=209&w=353&sz=6&tbnid=l2Z9KLaWHghD0M:&tbnh=70&tbnw=119&zoom=1&usg=__jiRo-FfgSrvRQ_Y2qAx1LlRoNoQ=&docid=Q7iD1uGvO8cbBM&hl=en&sa=X&ei=5XyFUeLDKYKwO6WhgfgO&sqi=2&ved=0CEMQ9QEwBQ&dur=3432
(this is a switching relay diagram but they work the same)

To get it ignition controlled you need;
an ignition controlled supply to contact 86,
85 to earth,
permanent supply to 30,
then new socket to 87.

The same system I used to use to run my fridge and split charge system on my caravans.


Edited by: Llanigraham

 

[Kenny R]

+1As Graham correctly points out, just because it says 14V on it, it will not magically switch when it reaches this voltage. And even if it did pull in at 14V, as with most relays, you would need to reduce the voltage below 50% ie 7 volts for the relay to drop out.

 

[Keith L]

Thanks for the interest guys, its caused quite a debating point. I will do some more digging and report back.

 

[Llanigraham]

On the Towsure website there is a "thing" you plug the cooler into, that then plugs into the socket and this cuts-off the cooler when/if the voltage drops to a certain level, possibly 11v.