Taylor-Dunn B0-248-TT, Operation, T Roubleshooting And Replacement Parts Manual, Page: 141 / 204

Electrical Troubleshooting
Charger Troubleshooting Page 3
TESTING THE CHARGING CYCLE
In typical installations, the charger will remain on for up to 12 hours depending on the state of charge of the
battery when the charge cycle was started.
A charger could remain on for longer than 12 hours if:
• The charging cycle is interrupted at any time during the charging cycle.
• Defective batteries causing a fluctuating DC voltage that confuses the charger.
• A brownout (drop in AC line voltage) during the charging cycle.
• An electrically noisy charging environment.
A charger could turn off in less than 12 hours, but still show symptoms of overcharging if:
• The batteries were not discharged to 50% before connecting the charger.
• The electrolyte in the batteries is too high (boil over).
• The electrolyte in the batteries is too low (excessive gassing or sulfur smell).
To test the charger to see if it is turning off correctly, monitor the battery
voltage and the electrolyte specific gravity during the charging cycle as
indicated below.
Specific Gravity
Using a hydrometer take the specific gravity reading of several cells, at 1 hour intervals while charging. If
the specific gravity of the electrolyte does not rise for three consecutive readings and the charger does not
shut off, then the charger is running too long.
Battery Voltage
Using an accurate 5-1/2 digit digital voltmeter, monitor the battery voltage during the charging cycle. Take
readings every 30 minutes. If the battery voltage does not increase 0.012 volts in two consecutive readings,
then the charger is running too long.