Inverter Settings; Setting The Communications Conditions - Omron SYSDRIVE 3G3MV User Manual

Communications
The 3G3MV Inverter has standard RS-422/485 and optional CompoBus/D
communications functions. This section provides information on how to
communicate over RS-422/485. For CompoBus/D communications in
detail, refer to the 3G3MV-PDRT1-SINV CompoBus/D Communications
Unit User's Manual (I529).
It is possible to control the Inverter, give frequency references, monitor the
Inverter status, and read and write parameters through communications.
A maximum of 32 Inverter Units can be connected and used as a simple
network system.
NoteThe RS-422/485 communications of the 3G3MV Inverter conform to the
MODBUS Communications Protocol and this protocol cannot be used
together with CompoBus/D communications protocol or any other com-
munications protocol. Only 3G3MV-Series products can be connected
as Slaves.
(The MODBUS Communications Protocol is a trademark of AEG
Schneider Automation.)

7-1 Inverter Settings

7-1-1 Setting the Communications Conditions

H Communications Time-over Detection Selection (n151)
·This parameter is used for monitoring the communications system.
·The set value in the parameter determines whether communications time-over detec-
tion will be performed with "CE" displayed if there is an interval of more than 2 s
between normal communications. The method to process the detected communica-
tions time-over is also determined according to the set value in the parameter.
·When a control signal (the RUN command, forward/reverse rotation command, or an
external fault signal) is input into the Inverter through communications, be sure to set
n151 to 0, 1, or 2. Then the system will stop in the case of a time-over detection.
If there is a communications failure, no control input will be operable. It will be, how-
ever, impossible to stop the Inverter if n151 is to 4 or 3.
Use a host program that monitors how the Inverter handles all control input signals, for
example, so that there will be no interval of more than 2 s between communications.
7-2
Chapter 7