Battery Isolator Test

MichaelOnTheClaraMae · Posted: Thu Oct 18, 2007 7:29 am Post subject: Battery Isolator Test

I know a battery isolator contains diodes that permit current to flow in one direction only. Power from an alternator and/or shore charger supplied to the power-in stud of the battery isolator flows to each of the power-out studs connected to each battery bank. Current cannot flow back from one battery bank to another battery bank.

Accordingly, there should be continuity between the power-in stud and each of the individual power-out studs. And in turn, there should be no continuity between one power out stud and another. Correct?

Thanks in advance for helping out the electrically challenged.

Sea Wolf · Posted: Thu Oct 18, 2007 8:10 am Post subject:

Michael-

You are correct.

Here are two sources that deal with testing a battery isolator:

Installation and Test Instructions for Norco Battery Isolator

RV Doctor Question of the Month Second Question

Joe.

MichaelOnTheClaraMae · Posted: Thu Oct 18, 2007 8:22 am Post subject:

Mine is indeed bad and I have a replacement on order. Thanks for your help Joe.

Michael

thataway · Posted: Thu Oct 18, 2007 11:21 am Post subject:

Consider that diode isolators cause a voltage drop of about half a volt--thus it is difficult to keep the battery fully charged.

A combiner, does not have the voltage drop, and it s a better solution for battery combining and isolation.

MichaelOnTheClaraMae · Posted: Thu Oct 18, 2007 2:06 pm Post subject:

I read that Bob and if I were putting together a new boat, a combiner is likely what I would use. But the Clara Mae has done great getting 5 years out of her original four 2-year batteries and always with power to spare. I have routinely run the fridge off of the two-battery bank for four plus days without recharging. So I am going to stick with the original configuration for now. Kind of a "don't fix what is not broken" approach. I, and I am sure others here on the site, appreciate the suggestion though.

Michael