Yamaha RS90K Manuel D'atelier page 140

Charging method using a variable voltage charger
Charger
YES
Adjust the voltage so that the
current is at the standard
charging level.
Set the time according to the
charging time suitable for the
open-circuit voltage.
Refer to "BATTERY INSPEC-
TION".
If charging requires more than 5 hours, it is advisable to check the charg-
ing current after a lapse of 5 hours. If there is any change in the amper-
age, readjust the voltage to obtain the standard charging current.
Measure the battery open-circuit voltage after leaving the battery unused
for more than 30 minutes.
12.8 V or more --- Charging is complete.
12.7 V or less --- Recharging is required.
Under 12.0 V --- Replace the battery.
BATTERY INSPECTION
AMP meter
Measure the open-circuit
voltage prior to charging.
Connect a charged and
AMP meter to the battery
and start charging.
Make sure that the current
is higher than the standard
charging current written on
the battery.
YES
NOTE:
Voltage should be measured 30
minutes after the machine is
stopped.
NOTE:
Set the charging voltage at 16 ~
17 V. (If the setting is lower,
charging will be insufficient. If too
high, the battery will be over-
charged.)
By turning the charging volt-
age adjust dial, set the charg-
ing voltage at 20 ~ 24 V.
Monitor the amperage for 3 ~ 5
minutes to check if the stan-
dard charging
reached.
If the current does not exceed
the standard charging current
after 5 minutes, replace the
battery.
2-49
INSP
ADJ
NO
current is
NO