Energy Meter Manual

3-16

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 *

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]