YOKOGAWA UPM100, User Manual

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3-3
IM 77C01H01-10EN
Procedures for Setting UPM100/UPM101 Functions
3
3.1 Basic Setting
3.1.2 Setting of CT Ratio
[Procedure]
1. Write a CT ratio to the two D registers in the table below. The data type is 4-byte floating
point.
2. After writing that value, write “1” to the setting change status register, D0072.
D Register Reference No. H No. Description Effective Range
D0045 40045 002C CT ratio (float, lower 2 bytes) 0.05 to 32000
(with 5 significant digits;
can be set to the second
place of a decimal point.)
D0046 40046 002D CT ratio (float, upper 2 bytes)
D0072 40072 0047 Setting change status
If other than 1: Invalid
If 1: Writing is executed
Default CT ratio: 1 (4-byte floating-point data: 3F800000)
[Example]
To set the CT ratio to 10.0:
For station number 01, use PC link communication (without checksum) and the random write
command as shown below:
If 10.0 is converted into a 4-byte floating-point value, the value is 4120 0000.
[Command]
[STX] 01010WRW03D0045, 0000, D0046, 4120, D0072, 0001 [ETX] [CR]
[Response]
[STX] 0101OK [ETX] [CR]
Note
• When the CT ratio is changed, already integrated values of active energy, reactive energy,
apparent energy, optional electric energy, and regenerative energy will return to 0.
• Set the VT and CT ratios so that [Secondary rated power] x [VT ratio] x [CT ratio] is smaller than
10 GW.