GE GFK0579B User Manual

Together, a Remote I/O Scanner and the  modules it serves make up a remote drop on
the Genius bus.  The remote drop may consist of one to eight Series 90–70 racks.

P

S

GENIUS BUS

ALL RACKS MUST BE AT THE SAME GROUND POTENTIAL

 RACK 7

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B

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A

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C

N

N

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 RACK 1

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B

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B

T

M

 RACK 6

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UP TO 50 FEET

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REMOTE DROP

 RACK 0

When there are multiple racks, the Remote I/O Scanner must be located in the first
rack (rack 0).  To link multiple racks in a remote drop, a Bus Transmitter (IC697BEM713)
Module in rack 0 is connected to a Bus Receiver Module (IC697BEM711) in the first
expansion rack.  Additional racks are also linked via Bus Receiver Modules.

All racks in a remote drop must be at the same ground potential.

The maximum total cable length from the first Bus Transmitter to the last Bus Receiver
in a remote drop is 50 feet (15 meters).  Since none of the daisy–chained signals (all at
the same ground potential) are broken at a rack, any rack can be independently
powered–down without affecting the operation of the rest of the system.

Regardless of the number of racks used for a remote drop, the maximum amount of
data for a remote drop is 128 bytes of inputs and 128 bytes of outputs (8 discrete points
represent one byte and 1 analog channel uses 2 bytes).