Bell Intercom System BSX User Manual

Page of 20
5
Connections to the Entrance Panel
All  connections to the entrance panel and doors are provided by the control PCB marked 'CTX';
if the unit is a two door system then there will be 2 of these boards, one for each entrance. 
Up to  16  push-buttons are wired to the control CTX816 PCB as shown on Diagram 2. It is
unnecessary to run a pair of  connections  for  each push-button; by using a system of '2 out of
8  combinations'  the number of connections is reduced to a maximum of 8. Up to 63 push-
buttons are wired to the PCB CTX864 as shown on Diagram 5.
The Service button is wired as a separate pair of connections to the terminals marked 'SERV',
or via the time clock as in Diagram 1 depending upon the Control used.
Electric Door Release
The Control PCB provides 2 alternative pairs of outputs for electric lock releases;
'FAIL  SECR':  Use these connections for  'FAIL-SECURE'  lock releases. These devices require
power to release the door and therefore will secure the door in the event of power failure.
'FAIL SAFE': Use these connections for 'FAIL-SAFE' lock releases and magnetic locks.Both of
these devices require continuous power to lock the door and thus will release the door  if  power
fails.
Both outputs are specified at 12v DC with a maximum  current consumption of 0.5A. For electric
lock releases of other types or  specifications  please contact  the  manufacturer  for  information
on interface adaptors.
Tone Output
This  output may be connected to a DC SOUNDER placed in the entrance panel or close by.
The output becomes active during  the operation of a push-button to re-assure the visitor that
the resident is being called, and also while the electric door release is being operated to signal
the visitor to enter.
The specifications of this output is 12V DC @ 100mA max.
Fire Services Switch
A  pair of connections marked 'FIRE' on each control PCB can be connected to a remote
keyswitch for use by the Fire Services. The  key-switch must have a single, isolated,  normally-
open contact. Operating  this switch  will  have  the  effect  of  permanently  releasing  the door.
If this facility is to be used the  electric  lock release employed must be of the continuously-rated
type.