Analog Voltmeter Problem

[Tom Keevil]

The voltmeter on our electrical panel reads around 16 V when the batteries are actually 12.4. At rest it sits on 11.4 V, rather than going all the way to the left. Is this broken, or is there some way to adjust it? I know we should get a digital one instead, but that's a future task.

[Guest]

Hi Tom:

My analoge meter reads 12.2 volts when the battery is really 12.68v. Couldnt tell what the true state of charge was. I gave up on it and added a Link 10 to monitor the house bank. Its been a great investment. I now have an idea whats really going on with my batteries. Sure its expensive but the peace of mind is worth it.

Another option is to buy a cheap digital meter and mount it permanently wired directly to the batteries with an 1/2 switch.

Boyd
s/v Tern
CD30 MkII
Fort Lauderdale.Fla.

[Mike Rodriguez]

I go by the colors. Red is bad, yellow is so-so, but when I'm green I'm golden.

Cheers!

[Carter Brey]

When my OEM voltmeter died, I replaced it with this Teleflex unit. Drops right in to the old 2" round hole in the DC panel, costs $24, works perfectly. For me, the fancy digital units are just too much expensive information that I don't need. Besides, like Mike, I like a little color in my life. Especially sailing off places like Greenwich, CT. Yeesh. Can you spell W-o-n-d-e-r-b-r-e-a-d?

http://www.boatersworld.com/webapp/wcs/ ... tId=357285

[jambalaya]

The difference between full charge (about 12.8 voldts) and 1/2 charge (about 12.2 volts) is only .6 volts. An analog meter simply cannot accurately represent this range. I use a digital meter and feel much more comfortable with the results.
Will
Jambalaya
CD30

[Kurt]

Blue Sea Systems also makes a nice panel mounted analog 8-16 volt that fits the CD27 factory panel quite nicely. While it's not as precise as a digital, it will still indicate the condition of a battery with a high degree of accuracy.

[slaume]

Battery management is new to me this year aboard the CD-30. We have two group 27 glass matt batteries and the Universal engine with the original charging system. We also have the original volt meter which never seems to read higher than the very low end of the green. I always feel like I am guessing about when and how much to charge the batteries while all the time worrying about power consumption. I have looked at the Link monitors and they appear to address all the issues. They also cost a good bit of money, which might be justified for the peace of mind they may bring. It also might be better spent on a solar panel. Is there a small digital volt meter that is just that and will fit in the original opening or even one that would need another mounting option? Even if I knew the exact voltage in my batteries, how long do I need to run the engine? It all seems like a guessing game to me. Even if I started to calculate the alternator output at a certain RPM into a certain amp hour battery at a given battery voltage I do not think I would have a very good idea of how long I needed to run my engine. So far we have experienced no problems but I am VERY careful with power consumption. We usually sail off our mooring and and often sail back on, so this leaves me wondering when and how long to run the engine. It also seems pretty ridiculous to run the engine just to turn a little alternator to slowly charge the batteries. One more definite question is weather I should be charging one battery at a time or if the selector switch should be on both. So how are you all managing your batteries? Thanks for the help, Steve.

[winthrop fisher]

Hey Tom...
i would get another one and check it agaist the first one, may be the first one is bad, that does happen....winthrop

The voltmeter on our electrical panel reads around 16 V when the batteries are actually 12.4. At rest it sits on 11.4 V, rather than going all the way to the left. Is this broken, or is there some way to adjust it? I know we should get a digital one instead, but that's a future task.

[rtbates]

Hey you have two batteries, correct? Look at the panel reading for both batteries. Pick one to use exclusively till it won't turn the diesel over. As it's being used monitor the panel meter and see where it reads just prior to and at such a low voltage it won't crank the diesel. Now you know pretty much what it'll do, ie what you can run and for how long. That should ease your mind a tad. Switch to the other battery and crank the diesel. I can run for days on one of our groups 27's w/o any charging and it'll still crank the 1GM. Granted we don't have a 12v refrig or microwave or 12v AC. What we do have and use are the usual cabin lights and fans, anchor light, running lights, nav instruments, CD player and a newly purchased 12V LCD TV. As an oldie I find these flat screen TVs absolutely incredible.

happy sailing

randy 25D Seraph #161

[slaume]

Golly, we don't even have TV at home! Well we do have a television set but no cable and not much of an antenna. We use it for movies. So with just lights, radio, auto pilot, oh yeah and pressure water I should be able to go for days. Okay then how long do I need to charge to get back to be able to go days again? It is all a mystery to me, Steve.

[Oswego John]

Steve and all,

While patient-ly (pun?) waiting in the doctor's office the other day, I was thumbing through a boating magazine. I happened upon an article about charging a boat battery(ies).

The article caught my eye because of it's novel method of producing electricity. We are all somewhat familiar with the solar cell and the wind generator. I don't know what you would call this gizmo. Maybe a water powered generator?

The thing was towed astern like a drogue. It could be used whether under sail or under power. I know very little about this system. I was getting into the nitty gritty details of it when the nurse announced that "the doctor would see me now".

Of course, when I came out of the doctor's office and tried to glom the magazine, someone else was reading it.

I got the impression that it ws a low power generator that had a prop which was driven by water as it was towed behind a moving boat.

Maybe someone else can fill in some of the unknowns.

Whatever, (as my hero Archie Bunker would say)

O J

[Neil Gordon]

The thing was towed astern like a drogue.

Sure, except unless you're moored in quite a current, it doesn't work when not underway. Underway, it also slows you down.

[Jim Davis]

Randy has hit the nail on the head. I would add a twist. Do this on a weekend that you are on board and not going anywhere. Unplug the cord from the pier, do not add to the battery. Live normally, use lights, TV, music even the laptop. Make it a true test. Then on Sunday see if you can start the engine with the battery you have been using.

Back when I was using Group 27s I would alternate, battery 1 on odd days, #2 on even days, now that I have a bank of golf cart batteries and refrigeration it isn't so simple. I can go three days before I have to charge them up. This is when the refrigeration hits the low voltage shutdown, I can still crank the diesel without the separate starting battery.

That said, there is nothing wrong with adding a digital meter, or Link 10 as well.

Jim Davis
S/V Isa Lei
CT 35

[Neil Gordon]

Back when I was using Group 27s I would alternate, battery 1 on odd days, #2 on even days, ...

I did that, too, when I regularly recharged every time I used the boat. That didn't work as well when I moved on board. I equalized usage but I also equalized drainage. I've changed my odd and even day practice to an odd and even month one. Battery usage is balanced but now I'm reasonably assured of only draining one of them between charges.

[Jim Davis]

Note that was when I was using Gp27s and no refrigeration. Now that I'm on a larger boat with most of the comforts of home I use golf carts for the house bank. We do not practice economy of use with electricity and as I said I can go three days on a hook using whatever we want before the low voltage shutdowns happen. First the laptop, the the refrigeration. Now I use a Honda 2000i to recharge-just lug into the shore power and the charger puts 40 amps in. Also we can use our 110 AC things at the same time. I also recharge when Sandy wants to use her hair dryer or vacuum. In a marina I use a plug in heavy duty timer so the charger is on only for a couple hours a day, the rest of the AC stays on.

My thoughts were more aimed at the weekend user, not the liveaboard or long distance cruiser. On the water generators I think you are right. From what I've seen they have more drag than a soft bottom rubber duck and don't put out that much. I will either use the Honda or run the engine for an hour or so.

Jim Davis
S/V Isa Lei
CT 35