GE VersaPoint IC220PBI002, User Manual

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GFK-1911B Chapter 4 Installation 4-15
4
The Profibus Cable Connector
Most Profibus devices, including the VersaPoint Network Interface Unit, provide
the Profibus standard female 9-pin D subminiature connectors. Cable connectors
are available from Siemens parts distributors as "Profibus 9-pin D connectors".
These connectors provide termination resistors and a switch on the connector to
enable/disable termination.
The connectors label the connections for the twisted pair as cable A and cable B.
The following table illustrates the proper assignment of wire to connector to pin to
signal.
Pin Signal
1 , 2, 7, 9 Reserved
3 RxD/TxD-P (receive/transmit data +), cable B
4 CNTR-P (control signal for repeater), direction control
5 DGND (reference potential up to 5V)
6 VP (supply v5V for termination resistors)
8 RxD/TxD-N (receive/transmt data -), cable A
Shielding the Profibus Cable
Cable shielding is recommended at higher baud rates. Cable shields must be
attached at each device via the connector shells.
When mounting the NIU in the cabinet, connect the cable shield of the connected
Profibus cable with a shield bus via cable clamps. Use an appropriate shield
clamp for this.
RxD/TxD-P (3)
DGND (5)
VP (6)
RxD/TxD-N (8)
RxD/TxD-P (3)
DGND (5)
VP (6)
RxD/TxD-N (8)
Red (B)
Green (A)