ZP3 Fire Control Panel Installation, Commissioning and Maintenance Manual
Page 94
REV 11 (ISS 08/03/2010)
Z-loop wiring parameters
These must be as specified in the Ziton ZP wiring Guide, see
Appendix A: ZP Wiring guide
on page
99 for more details.
As a guideline only
For a loop with sensors, callpoints, and interface units only, the total loop resistance must not
exceed 75 Ohms (i.e. 37.5 ohms for positive leg and 37.5 ohms for negative leg), and the
maximum cable length must not exceed 3000 metres.
For a loop with loop-powered sounders, this depends upon the number of sounders connected.
Assuming 100 sounders, the total loop resistance must not exceed 12 ohms, and the maximum
cable length must not exceed 1500 metres.
Z-loop functional tests
1. Connect all the loops to the panel.
2. Power-up the panel, and allow the panel to go through the self-diagnostics, device
acceptance, and automatic calibration.
3. Access the Setup/Points/Accept Points menu, and manually accept all devices online.
4. Carry out the following checks:
Identify the device addresses on each loop that are [1] the closest to the panel, [2] the
furthest from the panel (i.e. near the end of the Z-loop), and [3] about halfway along the Z-
loop.
In the maintenance/reports to screen/point analogues menu, check that the first
analogue value (the "Reference Value", V1) of each ZP device is within the range 208 - 216
counts, and within 5 counts of each other. For ZX, ZR or EX devices, check for the
appropriate levels as shown in Table 26.
If the Reference Value is substantially reducing between the beginning and the end of the
Z-loop, this is an indication that the wiring is out of specification, resulting in signal loss.
Incorrectly sized wiring, a loop that is too long, loose connections, or similar faults could
cause this. If this is the case, the fault must be found and rectified.
Data wiring RS485
Check that RS485 data cabling connecting panels together meets the requirements of the Ziton
ZP Wiring Guide (see
Appendix A: ZP Wiring guide
on page 99 for more details). As a guideline, this
must be high-quality, screened, data cable, with a maximum of 2000 metres of cable connected
in any one network.
The cable terminating jumpers on the communications boards must be set correctly. See the
appropriate equipment data sheets.
