User's Manual

6
Connections to the Telephones
The telephone connections are provided by the RELAY PCB in the control unit marked 'RLX'.
Each relay board has provision for 8 telephones , hence a 16-way system has two of these
boards and a 40-way system has five.
There are 6 connections to each 500X telephone and 7 connections for 500LX telephone;
a separate cable should be used for each telephone.
Dual Entrance Models
These models contain two control PCBs ( CTX ) each of which is connected to either entrance
exactly as shown in diagram 1 or diagram 4. The operation of the BSX from each entrance is
the same as for a single entrance model except it should be verified that the operation from one
entrance will inhibit operation from the other. However, an engaged lamp output is available on
the CTX864 board only.
Door Monitoring
For door monitoring the model 500LX telephone should be used. These telephones are to be
connected to the RLX864 boards with 7 wires. The control CTX864 has a terminal marked
'DOOR SW ' and this must be wired to a normally open door contact.
For door monitoring please ensure that you are using a control that includes the CTX864
and RLX864 boards (there is no provision for this facility on the CTX816 board)