Analogue Addressable Loop Wiring; Fig.3 - Typical Analogue Addressable Loop Overview - C-TEC CAST ZFP Installation, Maintenance & Operating Manual

CAST ZFP Analogue Addressable Fire Alarm Panel
5.9

Analogue Addressable Loop Wiring

Fig.3 below shows a typical analogue addressable loop complete with detectors, manual call points, loop-powered
sounders and ancillary devices. Connect the loop to the relevant connector block on the panel's Main 1 or 2-Loop
PCB (dependent on model) and terminate screens at the panel's earth bar as shown in section 5.10, Fig.4.
Fig.3 – Typical Analogue Addressable Loop Overview
Design issues - reducing faults and their consequences
To ensure a reliable system, it should be designed and maintained to local design and installation regulations. The
CAST ZFP panel has a short circuit protected loop driver fitted and also short circuit isolators fitted in every
CAST loop device. A single short circuit or open circuit fault will have no detrimental effect on the operation of
the system.
Note a critical design issue with any analogue fire system is the combined effect of loop resistance, loop
capacitance and the current demand of loop devices. Factors that influence this include loop length, cable diameter,
cable type and the number/type of devices. There are no strict rules regarding these factors as every situation is
unique. However, if the following general rules of thumb are followed, the loop WILL almost certainly

Absolute maximum loop length = 1km using either 1mm

Maximum of 255 devices per loop (maximum of 512 detectors / call points per panel)

If sounders are used
specification (see Appendix
The above SHOULD NOT be considered the maximum operating conditions for the panel as many other
permutations are possible.
Hint! ZFP Loop & Battery Calculator Tools are available for download on C-TEC's website in the
Support Hub to assist with system designs (available @
Page 15 of 60  Approved Document No. DFU5030000 Rev 4  Installation and Programming Manual
DO NOT fit more than the maximum circuit rating detailed in the technical
6).
Always refer to the supplied device instructions before installation.
Hint! Refer to www.c-tec.com
CAST range of compatible devices.
2 2
or 1.5mm cable.
www.c-tec.com).
for C-TEC's
work.