How long can I keep the Nav lights on without draining the battery

[LiquidAssets]

Ok, so I have a cranking marine battery(one of those diehard's from Sears). CCA is 665 and battery was brand-new this season.

A lot of my time on the water is spent just floating and listening to tunes. How long can I leave my nav lights on without chancing a dead battery? An hour? Couple hours?

I know I can start it every once in a while, but I was just curious. Any advice would be appreciated.

Cheers!

 

[haulnazz15]

Re: How long can I keep the Nav lights on without draining the battery

Usually as long as it's just a basic stereo and anchor light (you shouldn't have your nav lights on when not in motion) you should be okay for a couple of hours easily. Keep in mind that an alternator doesn't normally put out much of a charge at idle, so running your engine at idle won't recharge it too much. In any case, dual battery system with a deep cycle battery would be the ideal solution so that you could switch to the other battery and not worry about running down the main cranking battery. At a minimum, one of those small emergency jump-start packs might be useful if you run the battery down while anchored out.

 

[LiquidAssets]

Re: How long can I keep the Nav lights on without draining the battery

I don't need my nav lights on when not in motion? Not sure I want to be sitting in the dark without lights on......

 

[BTMCB]

Re: How long can I keep the Nav lights on without draining the battery

I don't need my nav lights on when not in motion? Not sure I want to be sitting in the dark without lights on......

Nav lights should NOT be on when at anchor. However, the stern anchor light SHOULD be on - just my take on the subject and I am no expert.

 

[45Auto]

Re: How long can I keep the Nav lights on without draining the battery

BTMCB is right. Your nav lights should not be on unless you are under way. If not under way, the only light that should be on is your anchor light.

Boat light basics here:

http://www.boatus.org/onlinecourse/reviewpages/boatusf/project/info2c.htm

 

[cwcollins06]

Re: How long can I keep the Nav lights on without draining the battery

Alright, dumb newbie question. I have a 17' Trihull Bowrider from 1977 and there's only one switch for the lights. How do I have my stern/anchor pole light on but not have my green/red nav lights on?

If they're supposed to be off I can just cover them with an empty dixie cup I guess, but I don't think I can have them on or off separate from each other...or maybe I have no idea what I'm doing (Occam's razor and all).

 

[QC]

Re: How long can I keep the Nav lights on without draining the battery

Many boats, mine included, are wired/switched that way and it sucks ^^^^ We both need to add a switch to isolate the all around from the bow lights.

 

[cwcollins06]

Re: How long can I keep the Nav lights on without draining the battery

Many boats, mine included, are wired/switched that way and it sucks ^^^^ We both need to add a switch to isolate the all around from the bow lights.

Eh...the dixie cup will work for now, lol.

 

[Home Cookin']

Re: How long can I keep the Nav lights on without draining the battery

Many boats, mine included, are wired/switched that way and it sucks ^^^^ We both need to add a switch to isolate the all around from the bow lights.

your boats are wired incorrectly. It should be a three way switch. Until that is corrected, two solutions are to cover the bow lights, or, to allay concerns about the battery, get a d-cell anchor light and use that (good to have as a back-up anyway).

You can run your anchor light all night on a good battery. Can't speak to a radio, too. and a simple radio uses less power than a CD or tape player.

 

[haulnazz15]

Re: How long can I keep the Nav lights on without draining the battery

I've never seen a boat which had the NAV/anchor lights tied on a two-position switch. Most use a three-position switch with NAV-OFF-ANCHOR positions. I've seen some that have a separate switch for each as well.

 

[Andy'sDelight]

Re: How long can I keep the Nav lights on without draining the battery

I don't need my nav lights on when not in motion? Not sure I want to be sitting in the dark without lights on......

Ignore that bad advice. You absolutely need your nav lights on when you are drifting or under power at night. If you are anchored then you need to have your all around/stern light on with the Port and stern (red and green) off.

As for the answer to your question, a cranking battery is designed to handle large short draws, such as starting an engine. They're not well designed to handle being slowly drained down by electronics. I would recommend you consider adding a deep cell batery stricty for electronics only and leave the current engine connected to your motor so you always know you'll start. A deep cell handles Nav lights, courtesy lights, Radar, GPS/Depthfinder, and stereo all night for me without issue. Simply on a cranking batter as you are, I would recommend no more than 2 hour stints without running the engine.

 

[cwcollins06]

Re: How long can I keep the Nav lights on without draining the battery

I've never seen a boat which had the NAV/anchor lights tied on a two-position switch. Most use a three-position switch with NAV-OFF-ANCHOR positions. I've seen some that have a separate switch for each as well.

I'll check it out the next time I'm on the boat. I never knew they needed to be on or off separately so I always just pulled the switch all the way out. Maybe it is three way, but I don't think it is. Obviously, with my small boat I can only think of once or twice that it has ever been anchored when it was dark, so maybe I've just never tried.

 

[rbh]

Re: How long can I keep the Nav lights on without draining the battery

But the question is about battery life though, you can do the math thing -(bulb wattage draw) OHMs law.

But the easiest thing is just to have a second fully charged battery for when the first one dies.

 

[LiquidAssets]

Re: How long can I keep the Nav lights on without draining the battery

Good stuff, thanks.

I actally do have a 3 way toggle switch for my nav/anchor lights. Never knew until now the purpose for that though.

I will look into adding a deep cycle battery. I actually have a portable ipod dock(4 AA batteries) that I use so I'm not draining power from the battery.

 

[haulnazz15]

Re: How long can I keep the Nav lights on without draining the battery

Ignore that bad advice. You absolutely need your nav lights on when you are drifting or under power at night. If you are anchored then you need to have your all around/stern light on with the Port and stern (red and green) off.

I think you misinterpreted his post. He DOESN'T need NAV lights on when anchored or when not in motion. He only needs a 360-degree anchor light on when anchored. I think he gets the point either way.

 

[Andy'sDelight]

Re: How long can I keep the Nav lights on without draining the battery

I think you misinterpreted his post. He DOESN'T need NAV lights on when anchored or when not in motion. He only needs a 360-degree anchor light on when anchored. I think he gets the point either way.

"Not in motion" is completely incorrect. Unless he is anchored or moored, he needs his nav lights on. Just because the boat happens to not be drifting while not at anchor does not mean he only needs an all around light. Nav lights warn other boaters that you are either moving or have the potential to move. An all around only alerts the other boaters that you are static in your position via anchor.

 

['78 Crusader]

Re: How long can I keep the Nav lights on without draining the battery

I've never seen a boat which had the NAV/anchor lights tied on a two-position switch. Most use a three-position switch with NAV-OFF-ANCHOR positions. I've seen some that have a separate switch for each as well.

My jet boat was wired with a two pos switch. I rewired the entire dash and now have the anchor and Nav lights correctly wired.

Also, I have some underwater LED's on the transom that look pretty darn sweet!!

 

[QC]

Re: How long can I keep the Nav lights on without draining the battery

your boats are wired incorrectly. It should be a three way switch.

To be clear, they are switched incorrectly. I get it, but trust me there are a TON of them out there like this. This ride is a 2001, and she has nice switches etc, but it is a two way toggle, and there is not one three way on the panel.

I've never seen a boat which had the NAV/anchor lights tied on a two-position switch. Most use a three-position switch with NAV-OFF-ANCHOR positions. I've seen some that have a separate switch for each as well.

Yes, I agree on all of that. FWIW, my last three boats, two bought new, were setup up incorrectly as two way. Three different, and smaller, manufacturers.

My ONLY point is that there are many users, I?m not one of them, that would never understand there is a way, or a time, to use only the all-around (anchor) light. If they have not read, or been to a course, or learned from some other method (iboats) they would not know the difference if their boat was switched as I describe.

 

[haulnazz15]

Re: How long can I keep the Nav lights on without draining the battery

"Not in motion" is completely incorrect. Unless he is anchored or moored, he needs his nav lights on. Just because the boat happens to not be drifting while not at anchor does not mean he only needs an all around light. Nav lights warn other boaters that you are either moving or have the potential to move. An all around only alerts the other boaters that you are static in your position via anchor.

I don't understand what you are saying. If you aren't anchored or moored, you have to be moving unless you found some enigma of the Earth where no wind or current exists and allows your boat to remain stationary on the water. In motion means moving, whether under engine power or not. I didn't say he could drift without any NAV lights.

 

[jrs_diesel]

Re: How long can I keep the Nav lights on without draining the battery

We're starting to split hairs here, but I'd like to clear up some confusion, based on the Navigation Rules (I'm in the Coast Guard).

Rule 3(h) Underway means that a vessel is not at anchor, or made fast to the shore (docked), or aground.

Rule 23(c) A power driven vessel less than 12 meters in length may, in lieu of the lights prescribed in Rule 23(a), exhibit an all around white light and sidelights (red/green)
*Rule 23 is for power driven vessels underway*


For the original poster. If your switch does not have the capability to select anchor or nav lights seperately, you could re-wire it with a second switch or replace the existing switch with a three way switch.