Introduction - GE Profibus - DP Bus Instructions Manual

I. INTRbDUCTlON
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This manual describes the optional 6KCV300PDPBl card for connecting of inverters and converters to
Profibus-DP networks.
This manual is intended for design engineers and technicians responsible for the maintenance, commissioning
and operation of Profibus-DP systems. A basic knoyledge of Profibus-DP is assumed and may be found in the
"Draft Standard DIN 19245 Part 3" manual.
7.1. OVERVIEW OF PROFIBUS-BP
Profibus-DP is a field Bus designed for a fast data exchange relating to sensors/actuators; the communication is
established between a Master central unit (PLC or PC) and Slave units, i.e. sensors, actuators, drives, etc.
The data exchange is cyclic; the Master unit reads the Slaves input data and writes the Slaves output data. The
Bus cycle time is shorter than the cycle time of the central unit; the Baud Rates for the GE Profibus-DP interface
card are from 9,6 kbit/s to 12 kbit/s according to Profibus-DP standard part. 3.
The total cycle time depends on the number of Slaves connected; the 1.5-Mbit/s Baud Rate allows 8 GE drives
to be polled in 6 milliseconds. The realtionship betiveen polling (cycle) time and the number of drives in the
network is propotional to the number of drops and the number of words sent.
For example, at 1,5 Mbit/s, the cycle time for a network with 24 drives is
6ms
8 drives
* 24 drives = 18ms
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0301
The physical support is the RS485 serial line; the mqx. number of Slaves connected to the Bus is 125.
There only one Profibus-DP interface card for the AV-300 and DV-300 drives:
,
- 6KCV300PDPB 1
Example of Mono-Master Profibus-DP system.
I
MASTER
< I
I
1
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SLAVE
SLAVE SLAVE
Profibus-DP allows a Multi-Master system as well. For further information please refer to chapters 6 and 7 of
the "Draft Standard DIN 19245 Part 3" manual.
INTRODUCTION