GE P485 instruction manual Modbus network configuration, Parameter Description Range

SOFTWARE OVERVIEW

Modbus network configuration

OVERVIEW When controlling a Modbus sub-network with the P485 it is important to understand functions during starting up. If the P485 starts scanning nodes on the sub-network, before data is received from the fieldbus control system (fieldbus master), values of ‘00’ may be transmitted to the nodes before data is updated the first time from the fieldbus.

See Input/output data during startup on page 8–4for information on how to block transactions until valid data is received.

SERIAL INTERFACE To be able to communicate on the Modbus network, various communication settings SETTINGS needs to be configured. To gain access to these settings, select ‘Modbus Network’ in the

Navigation window.

Parameter	Description	Range
Bit rate	Selects the bit rate.	1200 to 57600
Data bits	Selects the number of data bits.	7, 8
Parity	Selects the parity.	None, Odd, Even
Physical standard	Selects the physical standard. This setting	RS232, RS422, RS485
	activates the corresponding signals on the subnet
	connector.
Start bits	Only one start bit is supported.	1
Stop bits	Either one or two stop bits can be selected.	1, 2

P485 MODBUS TO PROFIBUS CONVERTER – USER GUIDE 4–13