Daktronics MS-2013 Portable LED Scoreboard - Manual (Page 18)

12 Battery Care & Charging
To operate the charger, simply plug the scoreboard's power cord into a standard 120 VAC,
60 Hz outlet. Red and green LED indicators on the charger, visible through holes on the
exterior back panel, indicate the recharging status. A label at this location also describes
charging levels.
Note: When the batteries are connected, they will continuously supply power to the
driver, even if the digits are blank. Make sure that the unit is switched ON only during
an event or when testing. At all other times, the switch should be in the OFF position.
The table below describes how the charger indicators operate:
Scoreboard Operating Condition
High Charge
Red ON
Green OFF
When just the red LED is on, it indicates that the batteries
are discharged and the charger is recharging them at the
BULK rate of 6 A (stage 1).
While the red LED is on, the voltage measured (with the
charger on) should be 11.8
–14 V.
If the red LED stays on for more than 48 hours, refer to the
Charger Troubleshooting Table.
Medium Charge
Red ON
Green ON
When both the green and the red LEDs are on, the unit is
charging at an ABSORPTION rate of 2-6 A (stage 2).
This mode of charging gradually "tops off" the batteries
and reduces harmful sulfating.
While both LEDs are on, the voltage measured (with the
charger on) should be approximately 14 V.
If both LEDs stay on longer than 48 hours, refer to the
Charger Troubleshooting Table.
Float Charge
Red OFF
Green ON
When just the green LED is on, the unit is charging at a
FLOAT rate of less than 2 A (stage 3). The batteries are now
90 percent charged and ready for use.
This "float" charging current will gradually decrease to as
low as 0.1 A over the next day as the batteries reach 100
percent charge. They will now be kept at full charge without
overcharging.
If the green LED stays on and the battery is known to be low,
refer to the Charger Troubleshooting Table.