Specifications

79 Publication 1794-SG002D-EN-P - May 2012
Section 2.2
Select FLEX Ex I/O Communication Adapters
and Distribution Method
Step 1 – Select:
the communication adapter for the ControlNet Ex network the coax barrier to
distribute into hazardous areas
The diagnostic capabilities and determinism of the ControlNet network make it
an ideal choice for distributing I/O into hazardous area applications.
The redundant media ControlNet Ex communications adapter
(1797-ACNR15) is high speed and capable of communicating with as many as 8
I/O modules for up to 128 I/O points.
The ControlNet Ex segment in the hazardous area must be protected from other
ControlNet segments in safe areas. Isolation can be achieved via two approaches:
by converting coax to fiber with a pair of fiber hubs/repeaters or by using a coax
barrier.
The combination of a ControlNet fiber hub (1786-RPA and -RPFM) and a
ControlNet Ex fiber hub (1797-RPA and 1797-RPFM) allows for flawless,
high-speed, deterministic data flow and messaging between hazardous and safe
areas. This combination functions as an intrinsically safe isolator between
hazardous and safe areas and can provide long-distance communication up to
three kilometers. It is best for longer distance and largest number of adapters and
I/O points.
An intrinsically safe network and I/O system installed in the hazardous area
allows your data to be gathered at its origin and transported out of the area with
minimum amount of wiring. Cable penetrations into the hazardous area, cable
trays, and conduit are all drastically reduced.:
Network Comparison by Application Requirement
Catalog
Number.
Description Agency Certification Intrinsically Safe Output
Characteristics
Intrinsically
Safe Power
Supply (V, -V)
See
page:
1797-ACRN1
5
Redundant media
ControlNet Ex
adapter
Class I Division 1 Groups A…D T4
Class I Zone 1 AEx ib IIC T4
16 position male/female
FlexBus connector:
U
o
≤ 5.4V DC
I
o
≤ 400 mA
P
o
≤ 2.16 W
L
o
≤ 10 μH
C
o
≤ 65 μF
U
i
≤ 9.5V DC
I
i
≤ 1 A
P
i
≤ 9.5 W
L
i
= Negligible
C
i
≤ 120 nF
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