Thursday, February 17, 2011
As so often happens while boating, technical issues forced me to change my plans at short notice. I woke up just before sunrise and my first uncertain steps were to switch on the inverter and fire up the ye olde Espresso machine in order to wake myself up. The little light on the Victron control panel blinked a warning orange at me and had to find my reading glasses and a flashlight to see the little print “Low Battery”. That surprised me, as the Xantrex monitor showed 100% charge but I realized that my voltage was 11.99v and that isn’t a good thing with 12 volt batteries, that actually means that they are almost depleted (12.75v is a full charge for mine). Since St. Martin is the place to buy boat supplies I decide to postpone my departure by a day so that I could find the cause of the problem and rectify it. My suspicion was that I had a bad battery in the bank and that it was pulling down the voltages on all the others; but I needed to buy a hydrometer (which is a simple device that measures the specific gravity of the battery fluid in each cell) and a load tester. After getting these tools I had to charge the batteries up to full and then let them rest for a couple of hours before measuring so I had to run the engine for hours during the day and then, when the charge process was complete, disconnect the batteries and let them settle overnight. Several of the batteries had very low electrolyte, including one where most of the plates were no longer covered by fluid, so I added water to all the batteries as well. This took all day.
 |  |  |  |