Ziton ZP3, Руководство по установке и обслуживанию

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Chapter 3: Field wiring
ZP3 Fire Control Panel Installation, Commissioning, and Maintenance Manual 59
For information on loop isolators, see “Line isolators” on page 123 in Appendix A
of this manual.
The Z-loop connects the ZP analogue addressable devices to the fire control
panel. It is a two-wire loop that supplies power to the connected devices, and
carries communication between each device and the panel. Loops must be wired
in correctly sized cable, and must be continuously screened.
Refer to Table 15 below. Cables must be shielded and shields must be
continuous i.e. connected through at each device. For Class A return loop wiring,
both ends of the shield must be connected to their earth terminals at the panel.
For Class B single-direction wiring, the screen must be connected to its earth
terminal at the panel end, and left disconnected at the far end.
Shielded cable may be two-core or multiple-core. If multiple-core cables are
used, only Z-loop wiring or the fire system DC wiring must be run inside the same
screen. Third-party cabling, for example public address and intercom systems,
must not be run inside the same screen.
Z-loops should, where possible, be separated from high-voltage cabling. They
must not run adjacent to high-voltage cable for any substantial distance.
Separation should be at least 100 mm.
z † ƒ s ‡ ‹ v ~ { r s s x {  x x s { | o  x “ o r o x p † s } | y r z { | o { s
The ZP line loop screen
connection must be kept as
short as possible to ensure the
best results for noise
immunity, which is a CE
requirement.
The adjacent illustration shows
two screen connections.
Option B (the preferred
method), has a shorter screen
connection even though this
results in longer plus and
minus terminal wires.
SCREEN
Option A
SCREEN
Option B