statpower charger/link 10

[karista]

I am mystified as to my charging systems readings. I have a Statpower 20 which is individually connected to the housebank (3 12v Batteries) and starter battery. My link 10 meter is connected to monitor the housebank! The boats refrigeration is on all the time and the boat is always plugged in to shorepower, (boat is docked behind my house). The mystery is that the link 10 shows a small but continous discharge of the housebank, yet the Statpower's remote panel show the batteries as "ready"  (green light-fully charged), yet I see on the Link 10, a small ongoing amperage depletion when the refrigerator is cycling on. The Statpower does not seem to make up this amperage depletion. Any insight of whats wrong with this situation? The Statpower has a temperature sensor connected to it also to eliminate temperature impact.

Bernd Mueller

[Stu Jackson]

C34 Electrical Systems

Bernd

It's not really that surprising.  What is happening is that the charger will ONLY put out its maximum amperage  when your batteries are depleted, and during the bulk charging phase.  Since you're plugged in all the time, your batteries are (reasonably) fully charged, and the charger's most likely on float, with low amperage and at 13.8 volts.

The charger is still putting out, but it's less than the draw of the fridge.  Remember, the bulk phase is limited within the charger's programmed algorithm by either battery voltage sensing or time.

If you leave the boat unplugged for a day or so with the fridge running, then go down and plug it in, it'll want to put out max current in the bulk charging phase.  In fact, you might be able to get it to do that by just either unplugging or turning off the charger (if your's is on a switch) for a short time.  

Just starting back on the bulk phase will boost the volts and amperage output of the charger.  However, if the batteries are up to 13.8 volts, the bulk phase won't last long.  Better to leave it for a day or so.

Essentially, in your situation, your batteries are fully charged and the draw of the fridge isn't enough to kick the charger back into the cycling through the three phases: bulk, absorption, then float, It's on float all of the time.

The difference in your Link 10 is the amp hours drawn out by the fridge any given day vs. the much less than 10 amps (probably less than 2) per hour being put back in by the charger.

Stu