Sennheiser Tourguide System 2020 Instructions For Use Manual page 29

Charging the receivers' built-in rechargeable batteries
Place the receiver into one of the charging
compartments for receivers (slaves) ´.
The LED
Color of LED
·
red
green
red (flashing)
yellow/
orange
Charging a completely discharged rechargeable
battery takes approx. 2½ hours at room temperature.
However, the charging process may take longer if:
the rechargeable battery is deep discharged and
first has to be reconditioned by a deep discharge
recovery charge,
the temperature of the built-in rechargeable battery
is over 43 °C or below 3 °C, since, in order to protect
the rechargeable battery, the charging process will
be interrupted until the temperature is again within
the admissible range (the LED
After the built-in rechargeable battery has been fully
charged, the LED
Notes:
An additional temperature protection prevents
overheating inside the charging case. If the
temperature inside the charging case exceeds
safety limits, the charging process will be
interrupted and will only be restarted when the
charging case has cooled down.
When not using the receivers for extended periods
of time, charge them about every six months in
order to prevent deep discharge damage to the
rechargeable batteries.
·
lights up (see table).
The built-in rechargeable battery is being
charged.
The built-in rechargeable battery is fully
charged.
The temperature of the built-in
rechargeable battery is over 43 °C
or below 3 °C.
The built-in rechargeable battery is
defective. Interrupt the charging process
and contact your Sennheiser agent.
·
lights up green.
Meaning
·
flashes red).
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