Yokogawa PR300 Power and Energy Meter - Manual (Page 53)

4-12 IM 77C01E01-01E
4.7 Demand Measurement (Optional Measuring
Function)
The PR300 (with the demand measuring function) can measure the average power or current during the
set demand period.
This section explains the example display of measured value, measuring range, measurement operation,
and example measurement. For setting conditions related to the demand measurement such as demand
period, refer to Section 3.8, “Setting Demand Measurement Conditions.”
Example Demand Display and Measuring Ranges
Demand power
Start/stop of
demand
measurement
and alarm release
Turns on during
demand
measurement
Turns on during demand alarm
Turns on during demand measurement
Turns on while the
maximum value is displayed
Demand power
Supplementary
unit
(refer to the
table on the right)
Secondary rated power ϫ 1.2 ϫ VT ratio ϫ CT ratio
6 W to less than 100 W
100 W to less than 1 kW
1 kW to less than 10 kW
10 kW to less than 100 kW
100 kW to less than 1 MW
1 MW to less than 10 MW
10 MW to less than 100 MW
100 MW to less than 1 GW
1 GW or greater
Measuring range
0.00 to 99.99 W
0.0 to 999.9 W
0 to 9999 W
0.00 to 99.99 kW
0.0 to 999.9 kW
0 to 9999 kW
0.00 to 99.99 MW
0.0 to 999.9 MW
0 to 9999 MW
Demand current
Start/stop of
demand
measurement
and alarm release
Turns on during
demand
measurement
Turns on during demand alarm
Turns on during demand measurement
Turns on while the
maximum value is displayed
Demand current
Supplementary
unit
(refer to the
table on the right)
Current range ϫ 1.2 ϫ CT ratio
0.06 A to less than 10 A
10 A to less than 100 A
100 A to less than 1 kA
1 kA to less than 10 kA
10 kA to less than 100 kA
100 kA to less than 1 MA
Measuring range
0.000 to 9.999 A
0.00 to 99.99 A
0.0 to 999.9 A
0 to 9999 A
0.00 to 99.99 kA
0.0 to 999.9 kA
The phase of the demand current
being measured can be switched for display.
Phase indication lamp
Demand Measurement Procedure
Equation: (Pt - Ps) ϫ (60 minutes ϫ 60 seconds Ϭ t)
Pt: Current integrated value
Ps: Integrated value at the beginning of the demand period
t: Demand elapsed time (data update period: 10 seconds)
Start demand
measurement Stop demand
measurement
Demand
period
Average
power
(current)
update
Demand measuring time (while the maximum demand value is retained)
Average
power
(current)
update