Fire-Lite LCD-80FC, Руководство пользователя

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EIA-485 Shield Termination Shield Not in Conduit
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Document 53244 Rev. A 03/14/08 P/N 53244:A
5.1 Shield Not in Conduit
The EIA-485 line allows the FACP to communicate with the LCD-80FC
Indicator. 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 indi-
cator if it is the first or only device on the EIA-485 line. If a second indi-
cator is connected, the shield leaving the first indicator must be left
floating. The shield entering the second indicator must be connected to
the three-gang box or Earth Ground terminal (P2-7) on the second indi-
cator. If additional indicators are connected, the shield leaving each
enclosure must be left floating and the shield entering each must be con-
nected to the three-gang box or the Earth Ground terminal (P2-7) on the
indicator.
EIA-485 Loop
not in conduit
Shield
Figure 5-1: EIA-485 Without Conduit
Connect the drain wire to the outside of the
FACP cabinet via a BX-type connector.
Shield Drain Wire
FACP Backbox
(+) EIA-485
(-) EIA-485
FACP
LCD80
F
s
h
l.
c
d
r
FACP
Indicator Indicator Indicator