pianotuna wrote:
Hi,
The "fact" is that after 90 minutes of driving the batteries showed themselves to be fully charged. Trailer charging systems are notoriously bad at charging. So if they showed fully charged in 90 minutes of lousy charging they are likely capacity damaged.
But, on the other hand, the idiot lights don't tell much of the story. We don't have proper documentation of how low they went, nor what method of charging happened at the campground--i.e. what converter is being used.
Every cycle "damages" the positive plate. No exceptions. Even a 5% discharge causes permanent irreversible harm.
mdfenley wrote:
Ok,maybe I am showing my ignorance, but how did he damage the battery? Batteries are designed to be charged and discharged. Leaving the switch to on, just meant he was utilizing the battery, as it was designed to do. The battery never fully discharged, so there is not any damage to the cells or plates that are in the battery. Guess I am just a little confused on everyones response that he damaged the battery.
Mark
It has become quite popular on this forum to bash battery and holding tank monitors. While the holding and fresh water tank monitors are not precision guages they do provide useful information if you take the time to do an approximate calibration. It does not take much effort to check battery voltage for different number of lights illuminated. For instance I know that when I am dry camping that the I should have all but one light lit in the morning and all should be lit in the evening after charging in the morning. These indicators tell me everything is as it should be and saves me getting my DMM out to check battery voltage. These indicators also quickly told me I had a battery that was not holding charge due to sulfation. You do not need to measure your battery voltage down to the mV level to determine battery health.
Dick
