Schneider Electric PM810 Manual De Usuario

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© 2011 Schneider Electric. All Rights Reserved.
63230-500-225A2
PowerLogic
TM
 Series 800 Power Meter
3/2011
Chapter 4—Metering Capabilities
37
Power Analysis Values
The power meter provides a number of power analysis values that can be used to detect 
power quality problems, diagnose wiring problems, and more. Table 4–6 on page 38 
summarizes the power analysis values. 
THD. Total Harmonic Distortion (THD) is a quick measure of the total distortion present 
in a waveform and is the ratio of harmonic content to the fundamental. It provides a 
general indication of the “quality” of a waveform. THD is calculated for both voltage and 
current. The power meter uses the following equation to calculate THD, where H is the 
harmonic distortion:
thd. An alternate method for calculating Total Harmonic Distortion, used widely in 
Europe. It considers the total harmonic current and the total rms content rather than 
fundamental content in the calculation. The power meter calculates thd for both voltage 
and current. The power meter uses the following equation to calculate THD, where H is 
the harmonic distortion:
Displacement Power Factor. Power factor (PF) represents the degree to which 
voltage and current coming into a load are out of phase. Displacement power factor is 
based on the angle between the fundamental components of current and voltage.
Harmonic Values. Harmonics can reduce the capacity of the power system. The power 
meter determines the individual per-phase harmonic magnitudes and angles for all 
currents and voltages through the:
— 31st harmonic (PM810 with PM810Log, and PM820) or 
— 63rd harmonic (PM850, PM870)
The harmonic magnitudes can be formatted as either a percentage of the fundamental 
(default), a percentage of the rms value, or the actual rms value. Refer to “Operation 
with PQ Advanced Enabled” on page 99 for information on
 how to configure harmonic 
calculations.
Table 4–5: Energy-per-shift recorded values
Quantity
Register Number(s)
Description
Shift Start Time
1st shift: 16171
2nd shift: 16172
3rd shift: 16173
For each shift, enter the minutes from 
midnight at which the shift starts.
Defaults:
1st shift = 420 minutes (7:00 am)
2nd shift = 900 minutes (3:00 pm)
3rd shift = 1380 minutes (11:00 pm)
Cost per kWHr
1st shift: 16174
2nd shift: 16175
3rd shift: 16176
Enter the cost per kWHr for each shift.
Monetary Scale Factor
16177
The scale factor multiplied by the 
monetary units to determine the 
energy cost.
Values: -3 to 3
Default: 0
+
+
H
2
2
H
3
2
H
4
2
+
x 100%
THD =
H
1
+
+
H
2
2
H
3
2
H
4
2
Total rms
+
x 100%
thd =