Purpose of Voltmeter

[workinprogress]

http://www.iboats.com/Voltmeter_8_18_Volts/dm/category_id.246616--cart_id.726255840--session_id.514569808--view_id.169226
This is quite possibly the dumbest question ever, but if one of you wouldn't mind answering it I would appreciate it. In the interest of conserving weight, I am attempting to start the motor and run several low draw accesories off of a single battery. I am concerned the battery will not have enough juice and I want to install a gauge to keep me informed of the level of charge the battery has at any given time. Is that the function of the gauge in the link I posted up top, or is that gauge designed to tell at what level an alternator is charging? Thanks for the remedial assistance.

[redneckredfishr]

Dude,

A voltmeter will indicate your battery voltage when your motor is not running if you have your ignition on, if it's installed properly, but this configuration will draw additional current. Once you start your motor, it will indicate your voltage based on alternator/voltage regulator output. As far as weight goes, a voltmeter does not weigh enough to affect your drag. Many factors come into play concerning voltage, and minimum voltage required to start your specific motor. If you want to keep it simple, go to Wal-Mart and buy a handheld Minn Kota LED volt gauge. I think they cost $10-$20.

Another thing you can try is to turn on all of your electronics while your boat is sitting in your yard, and experiment with time intervals. Consider the longest duration you will possibly run your electronics without starting your motor, then let your electronics run for that amount of time (while your boat is in your yard). If your boat starts after the duration, you shouldn't have much to worry about. You can even let your electronics run for longer durations to build your confidence in your equipment as it's currently configured.

I hope this helps. 006

Will

[workinprogress]

I must not have asked the question correctly regarding weight. For the record, I can see you shaking your head while typing about a guy who thinks the weight of the voltmeter might affect the overall position of his boat in the water. What I'm concerned about is the weight of adding an additional battery, which would allow me to put in a dual battery switch and eliminate any chance of winding up dead in the water from the battery charge aspect. Your suggestion about running all the accessories in the yard and seeing how long it takes before the motor won't start is a great idea. One more question. In an electrical system, I understand the ignition plays a big role. I have a tiller handle motor with a simple electric start button. In this case, isn't there in fact no ignition. Do I need to add one, maybe in the form of a battery switch. It would be just like the triple position battery switches (bat1-bat2-bat1+2) except it would be simply an on-off switch like this.
http://bluesea.com/category/1/products/6005

[redneckredfishr]

Workingprogress,

What kind of motor do you have? HP, Stroke, Manufacturer, Year?

As far as ignitions go, all motors have ignitions; however, they are designed differently depending on the type of motor you have. I don't think you need to install an ignition key lock for your boat.

Also, some tiller models can be started using a emergency rope. Remove your motor cover and look at the top of your motor to see if it is equipped with a raceway that you can wrap a rope around. If so, buy a rope and handle, and keep it in your boat. Of course, you'll want to test it before relying on it in a pinch.

Will

[NOTHING ELSE MATTERS]

Or a portable booster pack and ready to go.I keep one in my boat for the whole season and does not loose power.I give it a recharge in the middle of summer and i'm good to go.No second battery, no switches, not a lot of money and you can use it on your cars too.
Just my worthless 2 pennies.

[workinprogress]

S@%&t, I just lost a post I typed. Let me try it again. redneckredfishr--2007 Yamaha 25hp 2 stroke tiller handle--My motor is so small I don't have to remove the engine cover to find the pull rope, it is outside of the engine cover. That is one reason I am not terified (just concerned) about running out of juice out on the water--I can always jerk the pull rope. That being said, I fish with my 4yr old, and if I EVER wind up needing the pull rope and get him safely back to shore I will purchase the world's greatest $4billion 12V battery to make sure I never need the pull rope again.
I'm not looking to install any kind of locking mechanism on the boat, it is in my garage any time I am not using it. The possible ignition (in my case main battery disconnect) would be for electrical shutdown only. Keep your ideas coming. Thanks.

[yellowdog]

My Lowrance has a voltage indicator on one of the screens. Don't know if you have(or are considering) electronics on your boat, but maybe an option.

[Fillet1]

My Garmin GPS has a voltage meter as well. Thats the easiest way to go.

[Shakespeare]

A voltmeter is not a practical instrument to detemine battery charge except under certain conditions;

The battery and electrolyte must be at a specified temperature (80 deg. F) and the voltmeter must be a digital type that is capable of reading voltage in millivolts. There are cross reference tables that you can compare your sampled voltage against to determine charge. This isn't something that you'd normally do on the water.

The voltmeter in your link is probably more suited to tell you if the alternator is performing and/or if your battery has suffered from some sort of malfunction like a dead cell or a depleted battery condition. It's not accurate enough to indicate normal charge. You can probably determine "general" battery health but that's pretty subjective looking at an analog gauge and you'd have to have some history to compare your reading to. It's not a bad thing to have though as it does offer some information as you're trying to diagnose a problem.

If it is of any peace of mind, I use one battery for my motor starting, Nav lights, and my electronics; VHF and Garmin GPS/Depthfinder. I've sat in one place for hours with the electronics on and haven't noticed any issue when re-starting the motor (Suz. DF115). I'm not a total idiot though as I also have a deep cycle battery on board and a set of jumper cables. Although not recommended, you can start your motor off a deep cycle bat in emergency circumstances. I think I remember in one of your other posts that you have some trolling motor bats. Well there ya' go... there's your backup. If you have a VHF then perhaps someone could come to your aid if you're in dire straits.

Mike C.

[redfish74]

Hey Workinp, Dose your motor charge the battery while running. If so my buddys bass boat runs all day with one group 27 battery. He has two live wells and two fishfinder plus gps. He has no problems. Fish finders and gps draw very little. Live well and talking on vhf will draw a lot. Hopes this helps. 017

[workinprogress]

redfish74--Yes it does charge the battery. The alternator puts out 6A at WOT. I could use some help from someone on knowing exactly what that does for me. There are a lot of times I run the outboard to get to where I'm going, and if the fish are biting I might either anchor or use the trolling motor for several hours at a time without starting the outboard. Is 10-20 minutes of running the outboard between between 2-3 hour periods of not running it sufficient charging time at this alternator rating while running multiple pumps (3) most of the time to keep my battery charged enough to start the motor. (reference earlier post--I have a pull rope and a battery I can take off of the trolling motor for backup in case of a problem)
Back to my battery gauge question from earlier (thanks for the feedback), this is more like what I am looking for.
http://www.basspro.com/webapp/wcs/stores/servlet/SceneSevenDisplay?catalogId=10001&storeId=10151&langId=-1&productId=-80190&scene7Path=BassPro%2f594-661-00%3flayer%3dcomp%26wid%3d500%26hei%3d500%26fmt%3d jpeg%26qlt%3d100%2c0%26op_sharpen%3d0%26resMode%3d trilin%26op_usm%3d1.0%2c1.0%2c0.0%2c0%26iccEmbed%3 d0&sourceName=images2%2f500-000%2f594-661-00.jpg&type=0&linkEnabled=false
The problem is I can't find one like this that Teleflex makes, and I was planning on going with the Teleflex Sportsman series tachometer. It has a white outline, and I hate to mount 2 gauges that look completely different right next to each other.
http://www.iboats.com/mall/image/vendor/16/bigger/968300.jpg
I am also having trouble finding the correct sending unit for the tach. I'm sure I can talk to enough tech support people to find it, but can anyone who has already been down this road save me the time? Thanks a lot for all of your help.
What would you guys do about the different casing of the gauges?

[NOTHING ELSE MATTERS]

What would you guys do about the different casing of the gauges?




Spray paint them ?

[workinprogress]

NEM--C'mon, no way are you serious about the spray paint!

[workinprogress]

The black gauge seems to be the only battery charge meter I can find, I'm thinking about finding a tach that is the closest in appearance I can find. This is disapointing because I think the white faced gauge would look good.

[NOTHING ELSE MATTERS]

Yes, you can spray paint the plastic housing with plastic and vinal spray paint.Then clear coat it and you done.

[NOTHING ELSE MATTERS]

Why don't you go with regular volt gauge?It's the same think.The one on the picture you linked start from 8 volts the line next is 10 then 12 then 13 then 14 which should be your normal when you ran the motor then 16 and 18.When motor off, should show at least 12 volts in order to start your motor, maybe less cause your HP is not that big.All you have to do is watch the gauge.

[redfish74]

Your battery should start your motor many times if your battery is in good shape. What do you have on while fishing and sitting still? I realiy dont think you will hurt your battery. And like fillet1 said your gps or FF may have the volt meter you are looking for. At only 6 amps will take a while to charge your battery if you have been running very much ele. while fishing with out eng running.

[workinprogress]

I will be running a livewell supply pump (one pump supplying both livewells) and recirculation pump on each of the two livewells, as well as a gps. I have some experimenting to do, and someone please jump in here with some advice, but I'm not sure there is any reason to run all 3 pumps all the time. I'm not super concerned about this, because I can always add an extra battery, but who has 3 batteries on a j16? I don't want to make the boat so heavy that I take away it's best characteristic, namely the ability to run in shallow water. By the way, each of the 3 pumps only draw 2 amps.