Any ideas of a good 12V Power Outlet to connect my GPS?

[jonathan180iq]

One up, Mrlmd1.

I had a volt meter/temp gauge/clock hot wired to my battery for more than 3 months and never had any significant power loss. Even over extended periods of sitting.

It stayed backlit all the time. I can't imagine how the draw from something being turned off could being more than something that was on all the time.

[cayuse]

Completely apples and oranges, Jonathan. If your instrument package is backlit with 2mA LEDs it might pull a couple of amp-hrs out of your 18Ah battery after a month of sitting around. It'll never notice it.
OTOH, if the GPS is pulling 20ma for whatever reason (still pretty trivial in the 'real' world of toasters) you'll have a pretty sick battery after sitting for a month.
Easy to check tho. Just hook it all up, and insert a multi-meter in the circuit somewhere.

Cheers

[jonathan180iq]

True.
But I think with a constant backlighting, clock memory and constant temp readings, you're talking 5-8mA.
I'm sure that while charging, a GPS will be pulling more than that. But in the off position and once, charged, it can't be much more than negligible.

But, like you said, only way to know is to test it.

[jwright5]

Hey guys, a good general rule of thumb for anything that charges via a USB standard (so pretty much every phone and GPS unit) is to assume a maximum draw of 11 Watts from the unit, plus whatever inefficiencies are inherent to your charging adapter. So maybe 15 Watts with a safety margin or around 1.25 amps on the 12V leg per device.