Ziton ZP3, Installation Operation & Maintenance

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ZP3 Fire Control Panel
ZP Wiring Guide
ZP3 Fire Control Panel Manual
Page W - 14 UD1160.W Iss 6 (25/02/2005)
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W
3.6 Un-shielded cable
Unshielded cable should only be used where it is impractical to use shielded cable. An
example would be the upgrading of an existing system to a ZP system, where the cabling
already exists.
When the Z-Address Line is used with un-shielded cable, the panel should be set to "AVF"
mode. In this mode, some of the functional responses are deliberately slowed, in order to
maintain data integrity in an electrically noisy environment. Electrical noise, generated by
third party pulsing systems, can transfer into Z-Address Lines if the third-party cables are
adjacent to the fire alarm cables.
In some cases use of unshielded cable can cause spurious responses.
Important: Under no circumstances must an unconnected screen be left floating on a
cable. If cables with screens are used they must be terminated, as per
Section 3.5.
3.6.1 Rules for using Unshielded Cable
10. Z-Address Lines may be run in steel or plastic conduit or trunking, or fixed to walls or
supports without conduit.
11. Third party or mains power cabling may not be run adjacent to the Z-Address line or in
the same conduit or trunking.
12. The cores of multi-core cable may be used for several Z-Address Lines from the same
panel, as well as ZP approved sounders, and ZP system DC control lines.
13. Where multi-core cable is used, it must only be used for the ZP fire detection system
devices. Third-party cabling should not be run inside the same outer insulation 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.
14. Noise generated by an un-shielded Z-Address Line may cause interference into third-
party systems, such as intercoms.
15. Un-shielded Z-Address Line must be separated from high voltage cables by at least
300 mm, as per BS5839 Part 1.
16. Unshielded Z-Address line must be separated from all other cables by at least 50mm.
3.7 Loop Length
The Z-Address Line operates with a 2-core loop length of up to 3000 metres when no high
power devices are used on the line. High powered devices (E.g. Loop powered sounders)
draw more current and engineering calculation is required for specific line configurations to
ensure that the line resistance through various sections of the line does not cause the line
drive voltage at the end of the line to drop from 20 volts to below the specified detector
minimum of 16 volts. For current draws and minimum line voltages see the applicable
datasheets. Refer to Ziton if further assistance is required.