Incite Fire Taktis Vision, Инструкция по установке и эксплуатации

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Installation 3
Man-1161IN Rev.A
Taktis Vision Installation & Operation Manual
13
Due to the nature of the fire protection system, its design is biased towards inherent reliability and failure of a network
point, although possible, is very unlikely. Fire control panels also have substantial back up power systems, therefore,
the likelihood of a total power failure under operational conditions, is also extremely rare. A suggested tolerance
level of one point failure is therefore recommended.
To guarantee operation of the system with one point failure it is necessary to arrange the cabling such that the failure
will not introduce more than 1200 metres of cable between the two points which would be connected together by
the failure.
This means that the total cable length between adjacent cable segments should not be more than 1200 metres. It
is not important how the 1200 metres is made up i.e. it could be 100 metres and 1100 metres or 600 metres and
600 metres.
Using these general rules and the specified or equivalent cable types will provide a guaranteed performance of net-
works with plenty of tolerance.
In reality, the networked system will operate quite satisfactorily with longer cable runs and if a system is required
which is outside of the parameters specified, the manufacturer should be consulted for guidance on specific designs.
Cable Type
The cable type used for the network connection should be suitable for RS-485 applications and equivalent to the
ones listed below.
Up to 600 metre distance between panels:
Up to 1200 metre distance between panels:
Cable Entry
Contrary to earlier preferred methods of terminating the shield on shielded cables, today’s EMC noisy environments
require that the shields of these cables be bonded to earth at all points on the system.
The most effective method of achieving this is to use EMC cable glands, which connect the shield to the gland and
earth in a 360-degree ring. Simply stripping back the insulation of the cable and connecting “pigtails” to earth is not
recommended. Shield cable is connected at one end only.
When using this method it is also important to ensure that the gland body is electrically bonded to the panel enclo-
sure.
BELDEN
NUMBER NOMINAL OUTSIDE
DIAMETER NOMINAL
CAPACITANCE NOMINAL
IMPEDANCE VELOCITY OF
PROPOGATION
9271 6.1MM 40pF/m 124 Ohm 66%
BELDEN
NUMBER NOMINAL OUTSIDE
DIAMETER NOMINAL
CAPACITANCE NOMINAL
IMPEDANCE VELOCITY OF
PROPOGATION
9860 11.2MM 35pF/m 124 Ohm 78%