Yokogawa PR300 Power and Energy Meter - Manual (Page 39)

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<Toc> <Ind> <3. Procedures for Setting PR300 Functions>
IM 77C01E01-10E
3.5 Communication Setting
3.5.1 Protocol
[Procedure]
(1) Write a protocol value to the D register in the table below. The data type is integer.
(2) After writing that value, write 1 to the RS-485 writing status register, D0277.
D Register
D0271
D0277
Reference No.
40271
40277
H No.
010E
0114
Description
Protocol
RS-485 writing status
(D0271 to D0276 are
validated)
Effective Range
0: PC link
(without checksum)
1: PC link
(with checksum)
2: Modbus/ASCII
3: Modbus/RTU
4: Modbus/TCP *
1
5: PR201 original
If other than 1: Invalid
If 1: Writing is executed
Initial value of protocol: 1 (PC link with checksum)
*1: Modbus/TCP can be selected for the PR300 with Ethernet communication function only.
NOTE
• When Modbus/TCP is selected for the protocol, the baud rate, the stop bit, the data
length and the station number are fixed and unchangeable.
• When PR201 original is selected, the baud rate, the parity, the stop bit and the data
length cannot be set via communication.
[Example]
To set the protocol to 4 (Modbus/TCP):
For station number 01, use PC link communication (without checksum) and the random
write command as shown below:
[Command]
[STX]01010WRW02D0271,0004,D0277,0001[ETX][CR]
[Response]
[STX]0101OK[ETX][CR]