Hitachi DN 10DY Instruction And Safety Manual page 16

(3) Regarding recharging time (At 68°F (20°C))
Depending on the combination of the charger and batteries, the charging time will
become as shown in Table 4.
Battery
EB 9
EB 9B
NOTE: The charging time may vary according to temperature and power source voltage.
4. Disconnect battery charger from the receptacle.
CAUTION: Do not pull the plug out of the receptacle by pulling on the cord.
Make sure to grasp the plug when removing from receptacle to avoid
damaging cord.
5. Remove the battery from the battery charger.
Supporting the battery charger with hand, pull out the battery from the battery charger.
CAUTION:
When the battery charger has been continuously used, the battery charger will heated,
thus constituting the cause of the failures. Once the charging has been cmpleted, give
15 minutes rest until the next charging.
If the battery is recharged when it is warm due to battery use or exposure to sunlight,
the pilot lamp may light in green.
The battery will not be recharged. In such a case, let the battery cool before charging.
When the pilot lamp flickers rapidly in red (at 0.2–second intervals), check for and take
out any foreign objects in the charger's battery installation hole. If there are no foreign
objects, it is probable that the battery or charger is malfunctioning. Take it to your
authorized Service Center.
Regarding electric discharge in case of new batteries, etc.
As the internal chemical substance of new batteries and batteries that have not been used
for an extended period is not activated, the electric discharge might be low when using
them the first and second time. This is a temporary phenomenon, and normal time
required for recharging will be restored by recharging the batteries 2 – 3 times.
16
Charger
Approx. 60 min.
Table 4
UC12Y UC14YF / UC14F2
Approx. 45 min.
Approx. 60 min.