Hitachi uc 24yj Technical Data And Service Manual page 10

(2) Forcefully stops charging by means of battery internal temperature sensor:
As shown in Figs. 4 and 5, each of the applicable batteries is equipped with a built-in thermistor or thermostat
to detect the battery temperature. Charging is stopped when the battery reaches the charging stop
temperature even if the battery is not fully charged.
When charging a high-temperature battery, the thermostat or the thermistor automatically controls to wait
until the battery cools down and then start charging.
In most cases of Ni-MH batteries, charging may stop before the battery is fully charged because the
detecting temperature of the thermistor is set as low as 55˚C and the temperature rise is rapid when the
battery temperature is high (see Fig. 6).
Battery type
Ni-MH batteries
Ni-Cd batteries
Control of charging according to battery temperature
Model
EB 9H
EB 12H
EB 1222HL
EB 14H
EB 18H
EB 930H
EB 1230H
EB 1230HL
EB 1430H
EB 1830H
EB 2430H
EB 7S
EB 9S
EB 12S
EB 14S
EB 7B
EB 9B
EB 9M
EB 12B
EB 1220BL
EB 12M
EB 14B
EB 1820
EB 18B
EB 24B
When charging a high-temperature battery
When the battery temperature is over 50˚C, the
charge time lamp flashes red in 0.6-second intervals.
When the battery cools down to 50˚C, the charge time
lamp lights red or orange or green continuously and
starts charging.
When the battery temperature is over 55˚C, the
charge time lamp flashes red in 0.6-second intervals.
When the battery cools down to 55˚C, the charge time
lamp lights red or orange or green continuously and
starts charging.
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