volt meter

[maxum454]

I would like to know what is the correct range my volt meter should read when I turn my key to on position to check gages? I believe something is draining my batteries. I read 11 volts after I disconnect my shore power thus tuning off my battery charger. Charger has been on for several days to this point. My fridge runs during the week for 2-3 days until I take the boat out again. sorry so long, wanted to provide info though.<br />thanks for any input...

 

[Trent]

Re: volt meter

 

[McKenzie]

Re: volt meter

are you having problem with the battery dying or just curious? Unfortunately, the voltmeter at the instrument panel is generally inaccurate. With the length of wire between the battery and all the breaks and splices in between, the gauge usually reads lower than reality. It is best to check the battery with a multimeter at the battery itself. If you think something is draining it, hook up an ammeter in series with the positive battery cable. then pull and replace plugs and fuses until you find what is causing the problem. Do you have two separate battery banks on this boat? If you don't this is how i would make it. Have a battery for the house load. connect everything to it that has nothing to do with the engine. Then have a starting battery for the engine. wire engine gauges, starter, alternator, etc. to that battery. Connect the negative leads of the two banks together. then get either a on/off battery switch (NOT AN OFF/1/2/BOTH!!!!) or a continuous duty solenoid. I would use the solenoid because you can use it to automatically charge the house battery when the engine is running and to "jumpstart" yourself without the hassle. In case any of this is unclear, here is the jist of it, you want the house and engine electrical systems COMPLETELY ISOLATED. you want the batteries to discharge individually and charge together. The only time the batteries should be parrelleled is when the engine is running. If i failed to explain something well, feel free to ask.

 

[boat doc]

Re: volt meter

Under perfect conditions your volt meter will read whatever the voltage is of your battery, + or- a few 10ths of a volt. A lot of ignitions system out there will not fire unless they have at least 10 volts, so if you are above 10, and your alternator charges, I would not sweat it to much. by the way 12.5 is ideal. If you do not have an ammeter, an easier drain test is this:<br /><br />hook a test light up in series to your negative terminal of your battery. ie: diconect negative terminal, put one end your your test light to negative side of battery, and the other end to your negative cable. If your test light lights up, you have a drain, start pulling fuses, or disconecting components until ligh turns off. The brighter the light the bigger the drain. Use a 12v test light by the way

 

[maxum454]

Re: volt meter

Thanks to both for the reply. I will try this test to see if I have drain. I think it is my cd player. both batteries are new and my alternater is working fine. I have 2 batteries in a series one is a house and other is starter. I will check this weekend<br />thanks again