How low can a battery go?

11 volts is what I was thinking. The fridge (Waeco CF110) cuts out at less than this, hence the volt meter so I can cut it sooner.

Topend

Draining the battery too far will severely reduce it's life- even more so if it's not a deep cycle.
Low voltage won't however affect your Danfoss powered frige- the compressor is designed with a low voltage cutout and will NOT be harmed by running down to the low voltage cut off point....
There's lot's on the subject of discharging batteries if you do a search, however basically if you want your battery to last don't discharge to less than 30% charge remaining for a deep cycle battery..... starting batteries should be discharged far less than that or you'll be throwing them out very quickly indeed..
You can't really work JUST on voltage as that will vary tremendously depending on the amount of load when it's measured.
(approx 11.6v off load is dead FLAT, but under load it would be less volts)
Cheers

Yes agree that there will be no damage to frig's with a voltage cutout but some older ones don't have one. I should have reread my post to avoid confusion ;-))
On a not unrelated subject never connect the negative connection of any accessory direct to the battery negative terminal unless you are going to fit a fuse to both negative and positive legs.
The reason for this is that if for some reason the chassis/engine end of the negative/earth/ground cable is disconnected/broken/high resistance when you try to start the engine excessive currents will flow through the accessory, which usually means they are stuffed. I've seen quite a few HF radios fried because of this over the years as they usually have a decent size cable which can carry the current, but pretty much any accessory is susceptable.
The best place to connect the negative from any accessory is either at the engine/chassis ground end of the negative lead or preferably nearby.

nah www.batteryfaq.org is better :)

very handy feature - the adjustable cutout

remember the cutout is the voltage at the fridge so the actual battery voltage will be higher (more so after it has rested).

high is good for running of a starter battery
med is good for deep cycles
and low if for when you want to flatten the battery :)

They are coming to get you William and a good thing too!!!

NSW police are pigs that lie and are corrupt.

An auto electrician once told me not to get a deep cycle. Cost too much, can't buy them at an outback servo if you need a replacement and a normal battery will work just fine if you manage the amount of discharge.

and....
he'll sell you a new battery sooner!!!

I don't buy batteries from an auto electrician so his opinion is unbiased. I tend to agree with him as I have used Trailblazer and my Waeco CF110 for 8 or 9 years on standard batteries without a problem.

I have one of the battery over discharge protectors connected between the fridge and cig outlet, it cuts the fridge off automaticaly at 11.8 volts, they cost around $25 at K-mart if you can find them, or $30-$35 at 4x4 outlets. It's a good back up.

Hi Topend
I have a 110 and mine cuts out at 11.6 volts which I thought was a little hi as the waeco book says 10.6. I would be happy at around 11.0. I think you would be strugling with a solar panel if you live in the topend. I carry a small gen when on extended trips and just put it on once a day if not driving, this puts 10amps into the battery and runs fridge on 240 while i am running gen., usually a tank of fuel 4-5 hours. I turn fridge up while on 240 to pull temp down very low. Use 90ah optima deep cycle gell cell bat for fridge. Optima rep recon I could get 8-10 years from it but I dont think he is in the real world!

Cheers Steve