28 replies to this topic

[Adam]

I've been meaning to do this for a while, so I think it's about time I did it. I want a couple of 12v Power plugs in the back for when i go camping. And also some outlets to plug my inverter into aswell.

What I want:

1x Plug to plug inveter into under drivers seat.

2x Ciggie Lighter sockets In boot
1x Plug to plug inverter into.

Simple enough..

My questions are these:

Can i use existing amp wiring to run these accesories as well as the amp if needed? Or should i run another cable.

And, if no, what size cable/fuse should i run?

The inverter is a small one, have to update information on this when i get home.

[Xon]

Depends on the gauge of the amp wire, the rating of the amp and what you're planning to plug in (other than the inverter) to the extra sockets.
Personally I'd probably run a new wire for each outlet.

[Adam]

I assumed there would be many variables! Forking electricity, white man magic!

Ciggie plugs would be used for basic charging of appliances, maybe 12v lights e.t.c. Its hard to say the use. But its more a convenient locatin thing vs the one in the front.

Amp is something im considering replacing soon if i can find something small and cheap that does the same thing. (its a 4 channel, but only use 2 bridged)

So i guess running a seccondary power wire would be wise either way. It wouldnt need to be the same gauge at the amp wire would it? could be smaller? I think mines an 8G wire

[Scott]

will you be running the appliances and the amp at the same time?

id run a seperate wire if i was you tho, and make sure you use a decent fuse or circuit breaker would be better

[Adam]

Id like to have that option, so I think it's safe to say, I'll be running another wire!!

How do I determine fuse or circuit breaker rating?

[Xon]

Scott would be a better person to inform on fuse rating, but I would use a fuse rated at the same as the wire, eg 50 amp wire = 50 amp fuse.

[Adam]

That's what I always thought too, but I've also read that a fuse should be relevant to the load, though all adaptors that plug into ciggie lighters are generally fused anyway.

[Xon]

Relevant to the load? What are you going to do, swap out the fuse every time you plug something different in?

[Adam]

Haha I guess what I meant would be relevant to the highest load?

I dunno, electrical isn't my strong point

[RX25SE]

Adam,

Run a new line to feed the inverter and continue that to the back for the other plugs.

Near the battery fit a circuit breaker relevant to the load of the circuit.

Forget ciggie plugs for the inverter, use Merit plugs instead as they have better contacts and can handle higher loads without getting hot (high resistance generates heat).

To calculate the load of the circuit use this formula. W=IxV (W-watts, I-amps, V-volts)

Ex.

12v 100w globe

I=W/V
I=100/12
I=8.33 amps

Just add up all power (wattage) of all the stuff you want to run and divide by 12 to get the Amps.
The Amps will dictate the wire and breaker size.

[Adam]

Cheers God Jase!

The plan was to use those "quick clip" style plugs, but they all seem to be rated at 20 amps! Will suss out merit plugs! Though i also thought about a 50 amp anderson plug (though probably an overkill? but cheap)

I checked out the inverter yesterday, its only a small 300W inverter, came with a ciggie plug cable for anything up to 150W and a cable with a 35A Fuse and Cattery Clips for anything over that.

I guess i need to dertermine the max. power draw for the ciggie plugs. Ive eyed some "LED Spotlights" On ebay that are 10W and they are probably the highest drawing items i would use!

So going by that it would be

(300+10+10)/12 = 27 Amps(rounded up to decimal)

[RX25SE]

I use LED globes in cheap work lights. They draw about 0.3A but the light is only good for general area lighting.
Where you need to see, such as above the kitchen, I use 12v fluros. They draw about 0.55A and cost under $40 from camping shops.

I run my campsite off 2x 12v 20Ahr golf cart batteries which will run 2 fluros and 2 LEDs for over a week.
I also have 2 small fluro lanterns for the bedrooms. Each runs on 4xAAA batteries and runs for about 3 hours. Under $10each.




What are you running off the inverter? (they are not efficient as the inverter itself draws current in addition to the load)


27A is getting a little too much for a Merit plug.

[Adam]

I use LED globes in cheap work lights. They draw about 0.3A but the light is only good for general area lighting.
Where you need to see, such as above the kitchen, I use 12v fluros. They draw about 0.55A and cost under $40 from camping shops.

I run my campsite off 2x 12v 20Ahr golf cart batteries which will run 2 fluros and 2 LEDs for over a week.
I also have 2 small fluro lanterns for the bedrooms. Each runs on 4xAAA batteries and runs for about 3 hours. Under $10each.

I have also noticed that with the LED Lighting. But was attracted by the cheapness ~$20 I’m still very tempted to see how they go!

Generally I use a gas light, and the other lighting would be for emergencies/convenience.

What are you running off the inverter? (they are not efficient as the inverter itself draws current in addition to the load)

I use it to charge camera batteries at the moment, but would like the option to run other things if I wanted.

I’m sure I could probably get a 12v charger but at the time, the inverter was the best/quickest/cheapest option. And it means I can charge anything I need.

I’m assuming I can’t get a 27 amp breaker so bump it up to a 30?

http://www.ebay.com....=item336644dbe3

[RX25SE]

You could plug the charger into the inverter and measure the current draw out of the battery with a multi meter. Most go to 10A and I think you woukld be under that.

[Xon]

I run my campsite off 2x 12v 20Ahr golf cart batteries which will run 2 fluros and 2 LEDs for over a week.
I also have 2 small fluro lanterns for the bedrooms. Each runs on 4xAAA batteries and runs for about 3 hours. Under $10each.

Sounds like you have a fold-out house to go camping with?

[Adam]

But if I make the breaker suit the draw of the charger only, would that limit me to not using a larger appliance if i wanted?

[RX25SE]

But if I make the breaker suit the draw of the charger only, would that limit me to not using a larger appliance if i wanted?

Yes.

But it also makes for lighter wiring, connectors etc.

Small Anderson plug would be plenty and would also reduce the (small) voltage drop across the connector.
I use one on the camping fridge when it rus off the car. It draws about 9A.

Sounds like you have a fold-out house to go camping with?

Camper trailer.

[Adam]

Fair Call

How do i determine wire sizing?

[RX25SE]

Go 5mm or 6mm and solder all joints. That will be heaps.
Remember the earth will need to be the same size.

[Adam]

Awesome!

Thanks for all your help!

Edit:
Also, does earth need to run back to battery for this one? Or is to the body still fine?