The backup generator failed to start three times in the past year. In each case, the batteries were low. Pete was assigned to fix the problem.
Pete took “As Found” voltage measurements and noted the 12V batteries were at only 10.6V. He ran the generator, and measured the charging regulator output; no problem. He connected a portable charger system set to “low charge” (trickle) for 12 hours. Right after charging, he found the batteries were at 12.4V. The next