Bosch Appliances 3.5 manual Headset, Control inputs

2011-02 Installation and User Instructions 5 Call Stations

20.6.9 Headset

Connector:

3.5mm (0.14 inch) jack Electret impedance:

1 to 10 kohm

Microphone input sensitivity:

-47 to -32 dBV/Pa (tolerance ± 3 dB) Signal/Noise ratio microphone:

60 dB at -38 dBV/Pa (tolerance ± 3 dB) Earphone impedance:

32 ohm

Signal/Noise ratio earphone:

80 dB at max. output (tolerance ± 3 dB) Cross-talk (earphone to microphone):

<40 dB at -42 dBV/Pa and 1 kHz (tolerance ± 3 dB) Output power:

1 mW

20.6.10 Control inputs

Total cable resistance:

<1 kohm (with line supervision)

<5 kohm (without line supervision) Resistance detection (supervision enabled): Cable short circuit

<2.5 kohm

Contact closed

7.5kohm to12 kohm Contact open

17.5kohm to 22 kohm

Cable broken > 27 kohm

Resistance detection (supervision disabled): Contact closed

<12 kohm Contact open

>17.5 kohm External contacts:

Voltage-free closing or breaking contacts (relay

contacts, mechanical switches, mercury contacts etc.)

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Bosch Security Systems 2011-02