Door
s
ta
tion/power su
pply unit
s
Door station/power supply units
17
TwinBus built-in loudspeaker 1 4921
Device description
Built-in loudspeaker 1 4921 is integrated in an existing bell or letter box system in order to convert it into a TwinBus
door station.
Starting up
Connection
* Please note the red mark – see “Bus connections in the door station” on page
☞
16
.
** Wires 3 and 4 of the door station must be connected.
Circuit diagram:
Connection of the built-in loudspeaker
Note:
Use an additional mains transformer 1 6476 if you are operating the modular Portier door station with
more than 6 illuminated modules.
Operating elements
1. Door-to-apartment volume setting
2. Apartment-to-door volume setting
3. Bell button connection
4. Door bus connection/4-wire
Function
Activity
Result
2
1
3
4
00275-0
rot
rot
Adjusting the lis-
tening volume
Adjusting the
potentiometer
Adjusting the in-
tercom volume
Adjusting the
potentiometer
S0040-2
11
21 a1
a3 b
b
b
a2
N
L
4
3
2
1
K2 K3 K4 K5 K6 K7 K8 K9
K1
K
11 12
10
1 2 3 4
1 4921
KL1
KL2
KL3
KL4
KL5
KL12
1 7573
