American Dynamics RASI series, Руководство по установке

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SPEEDDOME OPTIMA HOUSING 8000-2692-01, REV. E
CONTINUATION OF INSTALLATION GUIDE
8 of 18
Cable Requirements
Data Cable
The table below shows requirements for
SensorNet, RS-422, and Manchester networks. For
more information about communication protocols
and cable networks, see Communication Protocols
and Cable Networks, 8000-2573-19.
Data cable requirements
SensorNet RS-422 Manchester
Cable type 1
unshielded,
twisted
pair* 2
shielded,
twisted
pair* 1
shielded
twisted
pair**
Wire gauge 22 AWG 22 AWG 18 AWG
Connection Non-
polarized
Polarized Polarized
Max.
devices on
line 32 10 3
* Power, data, and video cables can be ordered
separately or within a composite cable that can be
ordered in various lengths. Plenum-rated cables must
be used in indoor ceilings used for environmental air
return (called "other air space" in the National
Electrical Code). Order parts through your distribution
network.
Note: If you order cable from an outside source, wire
colors may be different.
** Belden 88760 (plenum), or Belden 8760 cable (non-
plenum) cable is recommended. Plenum-rated cables
must be used in indoor ceilings used for
environmental air return (called "other air space" in
the National Electrical Code). Order
cable directly
from Belden by calling 1-800-235-3361.
Power Cable
Plenum ceilings. Cable must be rated for plenum
and routed through electrical conduit. Use the
cable connection cover for conduit termination and
cable connections to the dome. Knockouts in the
cover accept ½" and ¾" conduit.
WARNING:
Do not run data and power
cables adjacent to or in the same conduit
as line voltage mains power.
Power cables. Make power cable lengths as short
as possible to minimize the affects of low line
voltages and outdoor cold temperature
performance.
Maximum cable length between a
Class 2 LPS (low voltage) ac source, such as a
J-box, and the dome depends on the ac line
voltage. See the tables below for maximum cable
lengths based on the worst-case low line voltages.
The line voltage must not go below the voltage
shown for the dome to be able to power up and
operate at the corresponding distances shown.
Typically cable distances are used that provide a
15% margin between nominal and low line
conditions. For example, if the nominal voltage
measures 120Vac, restrict the cable length to the
distance for .85 x 120 or approximately 100Vac.
Power Cable Requirements: Indoor Dome
The following table shows the maximum cable
distance between various indoor power sources
and the indoor SpeedDome Optima, for several
worst-case low line voltages.
These distances are for Sensormatic composite
cables, which use 18
AWG
ac power wires.
This table applies to domes produced after October
of 2001; distances are much less for earlier domes.
!