Quadnet Installation Instructions
9
Loop Loading
In order to allow a method of calculating the maximum loop loading that the system will support, each
device has a rating assigned in Alarm Loading Units (ALUs). A maximum of 175 ALU are permissible on
the loop. This only relates to the load presented in alarm and does not necessarily affect an input device.
The Quadnet OSP programming software automatically keeps control of the quantity and will provide
prompts if the limits are reached.
DESCRIPTION
ALU RATING
Sounder Low
0.5
Sounder Medium
1
Sounder High
2
Beacon
1
Loop I/O Module
1
Conventional Zone Module: Powered from loop
10
Conventional Zone Module: Powered remotely
1
Note: Whilst the system will operate a maximum of 800 devices per control panel, for compliance with
EN54: Part 2: 1997 Amendments 1 and 2, it is recommended that a limit of a maximum of 512 detection
devices is adhered to. This includes detectors and manual call points, but does not affect the number of
sounders or other alarm devices on the system.
