Modbus/Tcp Communications; Setpoints Configuration - GE 369 Communications Manual

CGCOMMUNICATIONS GUIDE
1.5

Modbus/TCP Communications

Note
369 MOTOR MANAGEMENT RELAY – COMMUNICATIONS GUIDE
RS232 port. Modbus is a single master, multiple slave protocol suitable for a multi-drop
configuration as provided by RS485 hardware. In this configuration up to 32 slaves can be
daisy-chained together on a single communication channel.
The 369 is always a slave. It cannot be programmed as a master. Computers or PLCs are
commonly programmed as masters. The Modbus protocol exists in two versions: Remote
Terminal Unit (RTU, binary) and ASCII. Only the RTU version is supported by the 369.
Monitoring, programming and control functions are possible using read and write register
commands.
Modbus/TCP Option:
When configured with the "E" Option, the 369 can connect to Ethernet networks via the
rear RJ45 connection, using the Modbus/TCP protocol as detailed in the document "Open
Modbus / TCP Specification" by Andy Swales, Release 1.0, 29 March 1999 (a search via the
internet can produce a free copy of this document).
This description contains information to the location of Setting registers for configuring the
369 for a LAN connection, and the physical connection of the 369. Information pertaining
to the application of an IED over Ethernet is beyond the scope of this manual and users
should consult their Network Administrators for configuration details.
The implementation of this option is for the intention of data retrieval and device
configuration. The 369 does not support firmware upgrade via this connection.

Setpoints Configuration:

The user needs to configure the following settings for interface to a LAN:
, and
SUBNET MASK GATEWAY ADDRESS
configures the octets as shown in the following example:
IP ADDRESS: "127.0.0.1"
"255.255.255.252"
SUBNET MASK:
"127.0.0.1"
GATEWAY ADDRESS:
IP ADDRESS OCTET1
IP ADDRESS OCTET2
IP ADDRESS OCTET3
IP ADDRESS OCTET4
SUBNET MASK OCTET1
SUBNET MASK OCTET2
SUBNET MASK OCTET3
SUBNET MASK OCTET4
GATEWAY ADDRESS OCTET1
GATEWAY ADDRESS OCTET2
GATEWAY ADDRESS OCTET3
. Each setting contains 4 octets. The user
SETPOINT MEMORY MAP
ADDRESS
0x101C
0x101D
0x101E
0x101F
0x1020
0x1021
0x1022
0x1023
0x1024
0x1025
0x1026
OVERVIEW
IP ADDRESS ,
DATA VALUE
(DEC)
127
0
0
1
255
255
255
252
127
0
0
CG3