Technical Manual UK.indd - CTC

BTU
electronic
DOORPHONE & VIDEO SYSTEMS
Expansion of doorstation BUS with audio selector
BTU for coupling doorstation up to 9
Possibility for expansion
up to 255 subscribers
Maximum of 9 additional doorstations
a3
BTU
a1
a3
a1
b3
b1
b3
b1
B3
B1
B3
B1
R
B2
b2
a2
R
B2
b2
a2
R
B
b
a
R
B
b
a
R
B
b
a
BSP 16
BSP 16
BSP 16
TLR 550M TLR 550M
TLR 550M
HT 522
HT 522
VT12
VT12
VT12
Doorstation in (Slave n)
Doorstation (Master) Doorstation in (Slave n)
CAUTION!
The connection between BSP 16 and BTU should be effected observing the
correct polarity. However, polarity may not be observed between BTU and
HT 522 (polarity safety).
! An individual transformer is
required for each doorstation.
A BTU audio selector is required for every additional doorstation.
Each internal doorstation (master) may be linked to up to 9 additional
doorstations (slave).
Due to the coded keypad , the BTU returns the BUS line
to the respective doorstation.
As long as this is activated, all the remaining doorstations will be shut off.
The red LED of the entrance speech element indicates the busy status.
The system is free for all doorstations, as soon as:
- 30 seconds have passed from the moment the receiver was unhooked.
- the receiver is back on hook, or the latest after 45 seconds.
Each doorstation forms an integrated unit.
7
7