Bellcall Digital Door Entry System
PD-083 Issue 3A
Installation and Operating Manual
Page 39 of 46
Diagram I – Phone Detail Wiring
The cabling to the phones can be any or a
combination of:- Star, Bus with spurs, or daisy chain.
The only limitation is that the voltage drop results in
at least 10V at the phone while ringing.
Use the tables in the “Cable Requirements” section
to estimate this
Using Cat5 allows 2 pair to be used for power and so
double some distances.
Daisy chain wiring is not recommended unless access can easily be obtained to all phones
for maintenance and repair. Junction and spur wiring allows a faulty phone or spur to be
isolated.
2
2
1
1
B
B
A
A
+
+
-
-
A
U
D
IO
A
U
D
IO
1
2
V
D
C
1
2
V
D
C
D
A
T
A
D
A
T
A
BC801
BSA
