Battery and Battery Meter Help

[Zamble]

I am trying to find a good battery meter. I am not sure of the age of the batteries, I bought the boat about a year and a half ago.

My boats details,
3 ACDelco 1150, 770 CCA each
1 Delco Voyager M30HMF, 625 CCA
1 Guest Charge Pro Model #2632, made in 2005. Supports 2 banks.

I have a 1977 28' Fiberform
2 Ford 302's, 175 hp Stringers.

I am almost paranoid about being out fishing all night and my batteries are dead. Either a battery has gone bad or just the juice was all used up.

On the water I use my fish finder, Humminbird 998C SI. 2 10 watt lights, and my electric flush head, electric water pump for my sink, some small overhead lights and radio.

I just want something that can monitor each battery for its individual charge, but I don't want to pay an arm and a leg.

Also if anyone has any suggestions on batteries it would be appreciated.

Thanks for any suggestions.

 

[5150abf]

Re: Battery and Battery Meter Help

Wow, they are a little salty, just went to iboats store and this is the least expensive one,

http://www.iboats.com/Paneltronics-...1738586--**********.492913321--view_id.356615

and they go way up form there, maybe radio shack.

I have a volt meter built into my Garmin which is nice.

 

[Silvertip]

Re: Battery and Battery Meter Help

Your boat doesn't have a voltmeter at the helm?? If not, install one. They are available right here on IBoats.

http://www.iboats.com/Dress-White-V...5182685--**********.148984338--view_id.135886


You only need one but to monitor all three batteries you would need a three position switch that lets you select which battery you want to monitor. You also need to realize that when the meter reads 11 volts the battery is essentially dead and will very likely not start a V8 engine.

 

[26aftcab454]

Re: Battery and Battery Meter Help

just remember electronics bought from iboats are no return/no exchangre/no refund
ask me how i know in a pm.

 

[Silvertip]

Re: Battery and Battery Meter Help

Pretty hard to screw up a voltmeter installation. Besides, the no return policy is true of many on-line retailers because they have no control over the installation of electrical components by those who either have no electrical experience whatsoever or because they try to be "creative" and screw things up in the process. Without any diagnostics, people "think" an electrical component is bad only to find out the new part doesn't work either and then want to return it. They also install a new component and find an associated problem is what popped the first one and therefore screwed up the new one as well since they really didn't fix the original problem.

 

[Zamble]

Re: Battery and Battery Meter Help

Thanks for the responses. My boat does have 2 volt meters at the helm. But like what you said soon as it drops to 11 no starting. The 4 batteries are wired 2 and 2. My battery charger is setup for 2 banks. They are on a battery switch, 1, 2, all, or off. I leave it on all, because the location for the switch is in the engine compartment. So I wanted something simpler. A gauge that shows the amount of charge on all the batteries.
I am thinking that when my batteries start going that I want to replace them with an 8D AGM battery. I really like the 480 min or so of reserve minutes. And then also getting a Dual purpose battery for starting.

 

[Silvertip]

Re: Battery and Battery Meter Help

You cannot get any more information than you already have. When you parallel two batteries into one bank the voltmeter will read the voltage of the one giant battery the two batteries in parallel form. If you hooked separate voltmeters to each battery they would both read the same. So you accomplish nothing. You already have a proper installation. Your no-start situation can be solved by using the battery switch as it is intended. Leaving it on BOTH when the engines are not running and you are using accessories is a good way to guarantee a no-start situation.

 

[jhebert]

Re: Battery and Battery Meter Help

...I wanted something simpler. A gauge that shows the amount of charge on all the batteries.

An accurate measurement of the voltage at the battery terminal will give you a good indication of the state of charge. You measure the voltage and then consult a table of voltage as a function of charge (and temperature) to deduce the charge. The most important parts of this measurement are the accuracy of the voltage measurement and the measurement of the battery at its terminals. For estimating charge you need to know the voltage to roughly plus-or-minus 0.1-volts in a roughly 13-volt system. This is an accuracy of 0.1/13 or 0.8-percent. This will require a rather accurate digital voltmeter, not some $30 marine store panel meter or even a $50 digital voltmeter from some tool vendor website. Find a good voltmeter with one-percent or better accuracy.

The next step is to connect the voltmeter directly to the battery terminals so that the wiring between the voltmeter and the battery is only carrying the current used by the voltmeter and nothing else. If you measure the battery voltage in any other location you will also be measuring the voltage drop in the power distribution wiring caused by the current flowing in the system to other devices.

This can easily be done, but you'll probably have to spend much more than you anticipate. A good voltmeter, the added wiring, and a good switch to select among multiple batteries could easily end up costing $400.

When you measure the voltage you will get the battery charge, but you will get no indication of the battery storage capacity, which is probably what you would really like to know. To estimate the battery storage capacity you need to discover its internal resistance. The simple test method for discovering a battery's internal resistance is to apply a load of know resistance and measure the voltage drops in the circuit. Unfortunately, this test method requires discharging the battery. Causing the battery to be discharged whenever you want to know its state of charge is a problem akin to the Heisenberg uncertainty principle. If you want to measure the internal resistance without discharging the battery a much more complex method of measurement of internal resistance has to be performed. You can obtain test equipment that can perform this method of measurement, but, again, it will be rather expensive. I would estimate about $1,000 or more for such a device. Whether or not you really want to put all of this battery measurement equipment on your small boat is up to you. It is not particularly cost effective if you only need one battery to work so you can get your engine started. It is cheaper just to have a back-up battery on-board.

 

[Silvertip]

Re: Battery and Battery Meter Help

I'll bet he knows exactly what to do now! -) But what he has is all he needs. Besides, he has batteries in parallel as well as a switch. No additional equipment is necessary. All that is necesssary is to use the switch properly. Those two voltmeters tell him whether or not both alternators are working and what the static and operating voltages are. If the voltage drop in either system is sufficient that it needs to be monitored, then there are other issues that need to be corrected.

 

[Tim Wagner]

Re: Battery and Battery Meter Help

Some depth finders also will display voltage.
I have a Lowrance sonar/gps unit and I have the battery voltage right on the screen.
it measures in tenths of a volt.
when fully charged, Im up about 13.5.
I fire up the motor and get it charging when it falls to 12.3.
Ill let it run for an hour and Im as good as I can be.

 

[Silvertip]

Re: Battery and Battery Meter Help

Tim -- I think you missed the point that this is a twin engine boat. Using the locator means you would need to flip a switch to select the desired battery to monitor, but during the switch the locator would shut off so you would need to power it back on. The only way that can be worked around is with a make before break switch.

 

[bruceb58]

Re: Battery and Battery Meter Help

when fully charged, Im up about 13.5.

A fully charged battery should read 12.6V. If you are reading 13.5V, either the engine is still running or you are measuring a surface charge.

To measure a battery properly, you need to let it sit for 30 minutes after charging.