GE Security ZP3, Инструкция по установке и обслуживанию

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ZP3 Fire Control Panel Installation, Commissioning and Maintenance Manual
Page 106 REV 11 (ISS 08/03/2010)
Shielding
Shielded cable provides the greatest protection against external interference, as well as
protecting other equipment from interference generated by the fire detection system.
Shielded cable must be used where possible.
Note: Shielded cable must be earthed at the panel at both ends and must never be left with the shield floating.
Rules for using shielded cable
1. Shielding includes cable with copper screens, Mylar covered, or Pyrotenax cable (MICC).
2. Shielded cable may be 2-core or multi-core.
3. Only Z-Address Lines may be run inside a screen, in order to qualify as Shielded.
4. Where 4-core shielded cables are used, 2 cores may be used for the Z-Address Line, and the
other 2 cores used for either ZP approved sounders, or ZP system DC control circuits.
5. Where multi-core cable is used, it must only be used for the ZP fire detection system devices,
attached to the same control panel. Third party cabling should not be run inside the same
shield as the fire detection cable. Examples are Public Address and Intercom Systems. Third
party cabling includes connections between ZP interface units and relays, etc. of other
systems.
6. The shielding must be connected-through at each sensor, line device, or connection, and
must be continuous through the complete length of cable. The connection must be by means
of a terminal.
7. Z-Address line must be separated from high voltage cables by at least 300 mm as per BS5839
Part 1.
8. Continuity of conduit, Pyrotenax, or shielding must be as per BS specification BS 5839 Part 1
(paragraph 24.5), and the IEE Wiring Regulations.
9. Insulated screened cable must be isolated from building earth except for connection at the
panel.
For Pyrotenax cable (MICC), which can pick up co-incidental earths at junction boxes, the building
system must have an effective earth bond between the parts of a building or buildings where the
system is to be installed. The building earth bond must be sufficient to prevent the fire system
from acting as an earth strap between the different parts of a building or buildings.
Shielding technique
Figure 66 and Figure 67 show the correct methods for using shielded cable.
The cable shield must be continuous, and must be connected through at detectors, or devices, or
at connections. Some detectors have provision for the shield connection, but in those without, a
connector should be used to join the shield.
Notes: Shields must be connected with a screw connector at each termination.
Earth continuity must be checked.
The addressable line outgoing and return loop must both be earthed.
For MICC cable, earth must be continuous at each connection or junction, in accordance with BS
specification BS 5839 Part 1 (paragraph 24.5), and the IEE Wiring Regulations.