Switching on the inverter which is powering a 600W heating element means
that the relay contacts will want to be rated for at least 50 amps
(600W/12V = 50A).

Maybe something like this Stancor:

http://www.alliedelec.com/Search/SearchResults.aspx?N=0&Ntk=Secondary&Ntt=5763007&sid=11D525125510&source=googleps

It'll handle 100A. The coil needs 3/4 amp to pull in.

Next we need a clock to power the relay coil. Something like this:

http://www.outdoorgb.com/p/12v_digital_timer/?utm_source=froogle&utm_medium=directory&utm_content=USA&currency=USD&country=USA

It'll handle up to 8A, so it'll power the relay's coil handily.

I leave wiring the two bits up to others. I can say that the relay makes a
mighty "clack" when it pulls in, so don't expect to be gently awakened by
the gentle gurgle of the coffee maker and the aroma of fresh coffee,
unless you're a heavy sleeper.

--
Mike "Rocket J Squirrel" Elliott
84 Westfalia: Mellow Yellow ("The Electrical Banana")
74 Utility Trailer. Ladybug Trailer, Inc., San Juan Capistrano
Bend, OR
KG6RCR

On 4/9/2009 2:09 PM John Carpenter wrote:

> Still, I have Dreams......
> While Sleeping in my bus,
>
> That I am awoken by the
> Smell of Freshly Brewed Coffee !!!
>
> I don't have to get up, reach up
> Or in anyway
> feel the chill of a cold Forest morning !!!
>
> My Mr. Coffee is
> Powered by my Inverter
> which in turn is activated
> by a 12v Timer.
>
> I have shortened the heating element
> in said Mr. Coffee.
> And, although it takes a little longer to percolate
> the water through the filter dish,
>
> It Also only takes 600 watts to operate.
> Easily running on my 800 watt Inverter.
>
> Ahh yes, the misses does call me
> Dreamin man
> Sez I just don't understand
> I guess that's my problem ! :o)
>
> PS: There also is those smaller commercial
> brewers that can be found in the better hotels.
> Not sure how many watts or who's they are?
> Now about the 12v timer to 120v Inverter?
> Any EE's out there? :o)