Running GPS while under sail

[harpguitar]

Hi,

I just installed the Garmin 440s in my 26'Westerly. I was wondering wether I can run it for 2, 4, 6, 8, 10, hours when sailing or whether it runs down the battery? I have a two battery system on my boat and I direct wired it to one of my batteries. I am a complete greenhorn when it comes to boat electrical issues. Any help would be much appreciated.

Rick

[sailingdog]

Harp-

It would really help if you said what size batteries you have.

If you're running the GPS, a VHF, running lights and a stereo...you will need a fairly big battery bank.

If you're just running the GPS... even most small battery banks will be able to handle it for 10 hours.

The current draw on a Garmin 440s is about 1.5 amps. So, to run it alone for 10 hours, you'd draw 15 amp hours. A Group 24 battery has about 90 amp-hours, of which you should only use 45 amp-hours... so you'd be able to run it for about three days @ 10 hours per day before needing to recharge the battery.

BTW, you really should read the post in my signature.

[wchevron]

yes, you can run it when sailing. it will run down your battery. how long you can run it depends on the amp draw of the gps and the size and amp hour rating of your battery and what else you have running/draining the battery at the same time. i run my 540s for 6-7 hrs. at a time and it doesn't drain much from the battery at all.

[SteveInMD]

The simple answer is that it's no big deal, run it all you like.

In general GPS systems don't draw much current, therefore you can run them a lot without a large drain on your batteries. However, some new ones with large sunlight viewable screens draw more than you might think. The Garmin website doesn't seem to put this information front and center for this unit...

https://buy.garmin.com/shop/shop.do?pID=8055

The current draw should be listed in you paperwork somewhere. We would also need to know about your battery capacity to know for sure. It's likely that you will be running other items the far surpass the draw of the GPS to the point where the GPS draw is almost irrelevant (such as refrigeration). But everyone's electricity use is different and if you are very conservative with power and you rarely run your engine or connect to shore power, every amp-hour counts.

[TRMN8R]

According to your manual, the spec is 15 watt draw. That translates to just over 1 amp if batteries are in fully charged state. Not knowing if you have other devices, ie VHF, AM/FM/CD, DS, KM, etc all of which you need to factor in to the ultimate draw on the battery. Also, you didn't indicate the rating on the battery that it's hooked up to direct?

[surftom]

Not sure if that unit has a "fishfinder"/Sonar - That takes more power if you have it on.
Just a thought

Tom

[gramcko]

You mentioned "direct connect to battery". Just a reminder, safest practice is a fuse very near to battery, or better yet through the electrical panel.

Anybody, is there a compelling reason to direct connect a GPS unit?

[sailingdog]

Gramcko-

I agree that the GPS should probably be wired with an in-line fuse at a minimum, and ideally through an electrical panel.

[sailortjk1]

Originally Posted by gramcko

Anybody, is there a compelling reason to direct connect a GPS unit?

Ease of installation??? Just guessing as to why it was done this way.

[jnsailing]

I would wire it to the cb panel - nav insts would be the breaker I'd use

John N.