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FLEX Ex Bus Isolator and Flexbus Connector
Publication 1797-5.13 - August 2001
I/O module capacitance value is cumulative. Ci (total) = Ci (I/O
module 1) + Ci (I/O module 2) + ...Ci (I/O module 8). Ci (total) must
be less than 65F. The limitation of eight I/O modules per isolator is a
functional limitation. Refer to table 2 of the appropriate I/O Modules
sections in this document (1797-6.5.6).
Application
The isolator type 1797-BIC/* functions as a galvanic isolation barrier
for signals between a non-intrinsic backplane bus and an intrinsic
safe backplane bus. The isolator must be installed in a safe or Zone 2
area.
Cover Plug for IS Backplane Bus
The 16-pole male connector for the FLEX Ex IS backplane bus is
provided with a cover plug. The cover plug can only be removed
when a 1797-TB3 terminal base, a 1794-CE1 or a 1794-CE3 cable is
connected. The connection must not be connected to any signals
which exceed the instrinsically safe values of the IS backplane.
Power Supply
The isolator is powered via a removable terminal connector with a
dc-voltage between 18V and 32V. Due to a failure in the power
supply a maximum voltage U
m
of 253V ac is permitted.
Repair
The isolator is not field repairable. Any attempt to open this device
will void the warranty and IS certification. If repair is necessary,
return this device to the factory.
Isolator
Restriction
1797-BIC and -CEC
Maximum of 8 I/O modules
