INFINITY ID2 INSTALLATION MANUAL.
Software Versions: PANEL 1.N & LOOP O.N
Approved Document No: GLT-211-7-1
Issue 1.9 Author: MG/NJ Date: 06/04/2016
PAGE 20
7.3 LOOP MODE - MAXIMUM LOOP LENGTH RECOMMENDATIONS
Some care must be taken when calculating the appropriate cable gauge for the system.
The main limitation is that during an alarm condition (maximum current draw), the voltage at all devices must be at
least 17 Volts with at least 5V of superimposed data signal.
The exact calculation equations are beyond the scope of this manual, because of the distributed load of the
sounders on the loop, but the following table gives a rough guide for maximum cable lengths at various current
loads for 3 different cable gauges
Maximum Loop Current (in Alarm)
500 mA
400 mA
300 mA
200 mA
1.0mm CSA cable
500m
625m
830m
1250m
1.5mm CSA cable
750m
930m
1250m
1870m
2.5mm CSA cable
1000m
1250m
1660m
2000m
EG. A system with a maximum load of 300mA using 1.5mm cable can have a maximum loop run of 1250m end to
end.
