E-Mon E-PS-S-HV-RTU - Manual (Page 23)

Chapter 2 Operating the
PowerSmart Socket PQM Demand Forgiveness (Cold Load Pickup)
PowerSmart Socket Power Quality Meter 23
Parameter 1/2
cycle
1
cycle
200 ms 1
sec
3 sec 10
sec
10
min
2
hours
Flicker Ч Ч
Symmetrical components Ч Ч
Phasors ×
1 Taken from the energy measurement channel
2 Only for power quality evaluation
3 Not affected by loss compensation
Demand Forgiveness (Cold Load Pickup)
Demand forgiveness (sometimes called cold load pickup)
avoids recording abnormal maximum demands in installations
with high pickup currents. Demand forgiveness is the time
during which the meter does not calculate or store the
maximum demands after a power outage.
The demand forgiveness time and the minimum outage
duration to be qualified for demand forgiveness are
programmable in the meter.
See Device Options and Mode Control in Chapter 5 on how to
program these settings in your meter.
Instrument Transformer Correction
Ratio and phase angle error correction can be applied to
external CTs and PTs to achieve overall metering installation
accuracy, or be used in any metering installation to optimize
the accuracy of the metering data.
The user can program up to 8 test points for both ratio
correction and phase angle error curves covering the typical
transformer operating range.
The PowerSmart Socket PQM is able to calculate the
transformer errors dynamically based on the transformer
performance characteristics and the actual CT current and PT
voltage signals appearing at the meter, to interpolate to the
actual measured operating point and to apply the
interpolated error corrections to the meter calculations.
See Instrument Transformer Correction Setup on how to
program the ratio correction factors and phase angle errors
for external CTs and PTs and enable correction in the meter.
See
Device Options and Mode Control on how to enable and
disable correction in the meter via the front display.
NOTES
1. When transformer correction is enabled, it is applied to
all instrumentation, billing and power quality
calculations and waveforms.
2. Transformer correction does not affect test LED pulse
outputs.
3. Transformer correction is not operational in test mode
regardless of the option’s status.