Notifier FDU-80, Руководство пользователя, Страница: 26 / 36

EIA-485 Shield Termination Shield Not in Conduit
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Document 51264 Rev A2 6/14/00 P/N 51264:A2
5.1 Shield Not in Conduit
The EIA-485 line allows the FACP to communicate with the FDU-80
Annunciator. The shield for the EIA-485 line must be connected to earth
ground at the FACP but must be left floating (no connection) at the
annunciator if it is the first or only device on the EIA-485 line. If a
second annunciator is connected, the shield leaving the first annunciator
must be left floating. The shield entering the second annunciator must
be connected to the three-gang box or Earth Ground terminal (P2-7) on
the second annunciator. If additional annunciators are connected, the
shield leaving each enclosure must be left floating and the shield enter-
ing each must be connected to the three-gang box or the Earth Ground
terminal (P2-7) on the annunciator.
E IA -4 8 5 Lo o p
n o t in co nd u it
S h ie ld
Figure 5-1: EIA-485 Without Conduit
Connect the drain wire to the outside
of the FACP cabinet via a BX-type con-
nector.
Shield Drain Wire
FACP Backbox
(+) EIA-485
(-) EIA-485
FACP
L
CD8
0
F
sh
l.
cd
r
FACP
FDU-80 FDU-80
FDU-80
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