Operation; Modbus Registers - Control Techniques Modbus TCP User Manual

Modbus TCP Module
8

Operation

The Modbus TCP Module must be controlled by a Modbus client (such as a PLC) which
complies with the Modbus Protocol Specification. For successful operation, the client must
also support all functions and interfaces described in this document.
8.1 Device Classification
The Modbus TCP Module is a Modbus server and must be managed by a Modbus client
over Ethernet.
8.2 Ensuring Safe and Successful Control
Data written to the device will remain in its registers until the data is overwritten or the
device is reinitialised. The device will not transfer successive duplicate commands to the
soft starter.
• If the soft starter is started via fieldbus communications but stopped via the keypad
or a remote input, an identical start command cannot be used to restart the starter.
• If the soft starter may also be controlled via the keypad or the remote inputs (as well
as via fieldbus communications), a control command should be immediately
followed by a status query to confirm the command has been actioned.
9

Modbus Registers

NOTE
All references to registers mean the registers within the module unless otherwise
stated.
9.1 Standard Mode
Command and Configuration Registers (Read/Write)
Register Description
40001 Command
(single write)
40002 Reserved
40003 Reserved
40004 Reserved
40005 Reserved
40006 Reserved
40007 Reserved
40008 Reserved
40009
Reserved
User Manual
Bits Details
0 to 3 To send a command to the starter, write the
required value:
00000000 = Stop
00000001 = Start
00000010 = Reset
00000100 = Quick stop (coast to stop)
00001000 = Forced communication trip
4 to 14 Reserved
15 Must = 1
Operation
9