Power Leaking and Electrolysis...

[svHyLyte]

Hopefully one of you electric's wizzards can offer some help....


We have a Link 10 (aka E-Meter) on our boat that we use to monitor the starting battery. The unit was installed in March 2002 and seemed to work fine until about a year or so ago when we began to see a constant amperage drain indication of approximately .3 to .4 amps. Negative amp-hours would accumulate and in short order the meter would indicate that we had less than 50% of capacity remaining although the voltage reading seemed unaffected. Upon asking our “Expert Electrician” (who had installed the unit) about this, he indicated that the unit had simply “lost its mind” and came over and “reprogrammed” the unit. In short order, however, the problem repeated itself.

After several visits, Expert Electrician insisted the problem was in our batteries—which were only two years old—which he replaced at no minor cost. With the new batteries the problem repeated itself within days. He then claimed that the unit again needed be reprogramed, to no avail, and next that the unit itself was using the power--.3 amps? When another friend had a look at our wiring, he discovered that moving one of the wires to the Link 10—black with an in-line fuse—would cause the display to begin blinking. Hitting the “Sel” button would stop that and return the display to 4-Green Bars (regardless of the indicated status of charge prior to the blinking business).

This past week we had our boat hauled out for a bi-annual bottom paint and discovered significant electrolysis damage to our prop-shaft (which had to be replaced), our prop (newly installed 2 years ago) and the strut that supports the prop-shaft. This damage tells me that there has been significant power “leakage” somewhere which I suspect has come from somewhere in the battery circuit that the Link 10 has been announcing. Is this likely to be a correct assumption? Is there any possibility that powering the unit from the battery that’s being monitored is likely to show .3 to .4 amps of drain?

The starting battery circuit goes from the starter battery to an On-Off switch and then to the starter. There is a hot connection to the house batteries through a solenoid controlled by an intermittent switch on the engine instrument panel (in case the starting battery dies but we still have power in the house bank). There is another hot connection to the house bank through an isolator so that when the engine is running our high output alternator—which connects to the house batteries—will recharge the starting battery as well as the house bank. The last hot connection to the starting battery circuit is an Echo Charger line from a Heart Freedom 20 Charger/Inverter.

As an aside, our Alternator regulator is a Heart “Smart Regulator” that works in tandem with a Link 1000 that is set up to monitor the house batteries (4 Trojan T-105’s in two banks). Lately I have noticed that with the throttle in any set position, the engine RPM has been bouncing up and down (as has the Tachometer from zero to whatever) indicating that the Alternator is being activated and deactivated at high frequency.

Any assistance with this will be appreciated.


s/v HyLyte