Yokogawa PR300 Power and Energy Meter - Manual (Page 70)

<Toc> <Ind> <4. PC Link Communication Protocol>
4-9
IM 77C01E01-10E
WRR Reads D registers on a word-by-word basis in random order
●
Function
This function code reads the statuses of the individual registers, on a word-by-word basis,
specified in a random order by the specified number of words.
• The number of words to be read at a time is 1 to 32.
• For the format of response in the event of failure, see subsection 4.1.2.
• The command shown below includes the checksum function. When performing
communication without the checksum, do not include the 2-byte checksum element in
the command.
●
Command/Response (for normal operation)
The response is returned in a 4-digit character string (0000 to FFFF) in hexadecimal.
ddddn: read data of the specified number of words
ddddn = character string in hexadecimal
n = 1 to 32 words
Number
of Bytes
Command
element
1
STX
2
Station
number
(ST-NO)
2
Number
of words
(n)
5
Register
number
1
5
Register
number
2
1
Comma
or
space
1
Comma
or
space
5
Register
number
n
2
01
3
WRR
1
0
Number
of Bytes
Response
element
1
STX
2
Station
number
(ST-NO)
2
01
4
dddd1
4
dddd2
4
ddddn
2
OK
…
…
…
…
2
Checksum
2
Checksum
1
ETX
1
CR
1
ETX
1
CR
Command (continued)
●
Example
Read the voltage-1 (register symbol: V1 L and V1 H) and current-1 (register symbol: A1 L
and A1 H) of the PR300 at station number 01.
The register numbers for voltage-1 are D0027 and D0028.
The register numbers for current-1 are D0033 and D0034.
[Command]
[STX]01010WRR04D0027,D0028,D0033,D003405[ETX][CR]
The data 800V for the voltage-1 and 50A for the current-1 will be returned in response to
the command above.
[Response]
[STX]0101OK000044480000424882[ETX][CR]
800 [V] and 50 [A] in decimal. See the Note below.
Note: To use the response data as the reading, reverse the order of the upper and lower words.
Voltage-1: floating-point hex data 0000 4448 → (reversed) → Hex 4448 0000 ⇒ Decimal 800
Current-1: floating-point hex data 0000 4248 → (reversed) → Hex 4248 0000 ⇒ Decimal 50