Serial Communications (Communication); Communication Via The Rs485 Serial Port (Rs485); Communication Via The Sbi Bus Field Card (Sbi) - GE AV-300i User Manual

1.13 SERIAL COMMUNICATIONS (COMMUNICATION)

1.13.1 Communication via the RS485 Serial Port (RS485)

The used communication protocol, called Slink4, allows a multipoint network.
See the specific manual for further details.
The Drive address can be defined via the Slink4 address parameter.
The address change is performed by writing the 105 parameter, SLink4 address, and by saving the new value.
The address becomes active after the Drive has been switched off and on.
Via the S_link4 command a temporary address change is also possible.
The RS485 serial line is a Half-Duplex line, where the data can not be transmitted and received simultaneously.
It happens sometimes that during the transmission to reception switching phase the Master (PC or PLC)
reaches the reception condition after the Drive has already started to send its data package. As a conse-
quence, the package received by the Master is not correct.
In order to avoid such an inconvenient, it is possible to use the SLink4 res time parameter, through which it is
possible to set a delay time on the Drive response in case of problems during the Tx to Rx switching on the
Master.
Description:
COMMUNICATION

1.13.2 Communication via the SBI Bus Field Card (SBI)

The communication with the SBI Bus field option cards (Serial Bus Interface) is performed via two channels:
· Synchronous or Process channel (PDC Process Data Channel) for a cyclical value interchange.
· Asynchronous or Configuration channel for a low priority access to all the Drive parameters.
As for the data exchange modes between the SBI card and the Network see the SBI card documentation.
The process data exchange between the Drive and the SBI has the following structure:
The interface is made of six writing Words and six reading Words.
The source Drive parameter has to be defined for the six Words
transmitting the data from the Drive to the SBI.
Six Words move the data from the SBI to the Drive.
These can be found in the source selection lists.
For more information to see the following documents for related information on SBI:
GEI 100422 for 6KCV301PDP33 card
GEI 100435 for 6KCV301DNET
Ch.1
132
GEH-6641E
RS485
SLink4 address
SLink4 res time
—————— Function Description ——————
Response delay (in milliseconds, msec)
'Drv -> SBI word'
'SBI -> Drv word'