Ziton ZP3, Руководство по установке и обслуживанию

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Appendix A: ZP wiring guide
ZP3 Fire Control Panel Installation, Commissioning, and Maintenance Manual 123
ÿ
1
2 3
4
1. Control Unit
2. Detectors 3. Loop
4. Spur
See Figure 60. Single direction wiring with spurs provides protection against
open circuits and earth leakage.
ÿ
1
2
3
1. Control Unit
2. Detectors 3. Spur
Line isolators are devices installed on the Z-Address line to monitor for short
circuits on the field wiring. These devices keep up to 93% of the line operational
in the event of a short circuit. Line isolation can only be utilised when Style A
wiring is used. They must be installed in accordance with the requirements of
BS 5839 Part 1.
See Figure 61 for a schematic of line isolator usage. Isolators are installed on the
loop at intervals. A short circuit on the loop wiring causes the isolators on each
side of the short to disconnect the damaged section of cable. This removes the
short from the loop, allowing the remainder of the loop to function normally.