Sennheiser IS 150 Notice D'emploi page 20

Charging the accuplug / charge indication
To charge the accuplug, insert the receiver containing the accuplug into the
storage and charging compartment . The charging process is indicated by
the LED . Switch off the receiver before charging the accuplug!
A second BA 151 accuplug can be charged in the charging compartment
. This charging process is indicated by the LED .
When the accuplug becomes weak (noise interference and sound
distortions are sure signs of a weak accuplug), switch off the receiver and
recharge the accuplug. (If necessary, use a second accuplug to listen
while the first accuplug is being recharged.)
Recharge the accuplug immediately when it is flat. If the accuplug is flat
but is left in the switched on receiver, this reduces the service life of the
accuplug („total discharge").
As far as possible, use the full capacity of an accuplug before your
recharge it. Frequent short discharge and recharge cycles prematurely
reduce its charging capacity.
Charge the accuplug for 24 hours before you use it for the first time!
NOTE
Charging in the charging compartments and works even when the
transmitter is switched off as long as it remains connected to the mains!
The transmitter is switched off when you recharge the receiver
containing the accuplug in the charging compartment !
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