Precision UK CPX-A Area Alarm Manual page 2

Introduction
The CPX-A area alarm panel is designed to monitor high & low pipeline pressure on
up to 6 gases, using volt-free, normally closed, contacts on pressure sensors
mounted in the pipeline downstream from the final Area Valve Service Unit (AVSU).
Each gas has a green normal, red high pressure and low pressure lamps. The panel
also has a green power on lamp and a red system fault lamp, together with a
mutable audible alarm. In addition, the panel has small status Indicators to show how
the panel is connected, and the status of the connection.
The CPX-A can also receive and transmit data from & to the MEDCON bus as used
by the CPX-P plant alarm system. Note. An additional adaptor, which plugs into the
main PCB, is required for operation with the CPX-P system.
About this manual.
When you see this symbol, the associated text in bold type refers to
something which may cause danger or damage.
Mounting.
Remove the front cover by removing the 2 M3 screws & lifting the cover clear.
Disconnect the earth cable. Remove the PCB by removing the 2 M4 earth screws on
the lower edge of the PCB and releasing the 2 clips on the upper edge. Unplug the
mains flex.
NOTE. Always ensure that you are in contact with earth when handling
electronic components to avoid damage by static discharges.
If cable entry is from behind the panel, remove the two knockouts in the back of the
panel. Mount the panel with the TOP label uppermost, using the 4 holes
provided. Mount the termination box (if used) adjacent to the pressure switches.
Plug the connectors on the flexes onto the pressure switches. Connect the 3 core
screened cable from the alarm panel into the terminals marked A, B & C, ensuring
that the screen is clamped using the copper clip provided.
Cabling
The following connections are required:-
A 240 volt 50/60 Hertz supply, fused at 3 amps.
WARNING. This equipment is not suitable for connection to an IT power
system. A readily accessible means of disconnecting the supply must be
provided. The maximum prospective fault current must not exceed 1500 amps.
If the panel is to receive data directly from pressure switches, a 3 core screened
cable, minimum 0.5 square mm, is required between the panel and the termination
box.