CET Electric Technology
40
4.2.2 Energy Measurements
The PMC-53A-E provides Energy parameters for active energy (kWh), reactive energy (kvarh) and
apparent energy (kVAh) with a resolution of 0.1 and a maximum value of ±99,999,999.9. When the
maximum value is reached, the energy registers will automatically roll over to zero. The energy can be
reset manually through the Front Panel or via communications. Further, the kWh/kvarh Import and
Export for Per-Phase and Total, and the kVAh for Per-Phase and Total can be reset via communications.
The PMC-53A-E provides the following energy measurements:
Per-Phase & 3-Phase
kWh Import/Export/Net/Total
kWh Import/Export of TOU T1-8
kvarh Import/Export/Net/Total
kvarh Import/Export of TOU T1-8
kvarh of Q1/Q2/Q3/Q4
kVAh
kVAh of TOU T1-8
Table 4-3 Energy Measurement
4.2.3 Interval Energy Measurements
The PMC-53A-E provides Interval Energy measurements of kWh Import/Export, kvar Import/Export and
kVAh. The Interval Energy measurements represent the amount of energy consumed during the last
completed interval as defined by EN Period. The Interval Energy Measurements can only be retrieved
through communications and are not available on the Front Panel or Web Interface.
The Interval Energy Period (EN Period) setup parameter can be programmed from the Front Panel, Web
Interface or through communications and allows the user to specify the interval for which the real-time
energy consumption should be accumulated. Please note that changing the Interval Energy Period
would clear the present Interval Energy measurements.
4.2.4 Demand Measurements
Demand is defined as the average power consumption over a fixed interval (usually 15 minutes) based
on the Sliding Window method. The PMC-53A-E provides Present Demand and Predicted Demand for
Ia, Ib, Ic, kW Total, kvar Total and kVA Total, updated once a second, as well as Max Demand for Ia, Ib,
Ic, kW Total, kvar Total and kVA Total of TOU Tariff 1 to 8 in This Month (Since Last Reset) and Last Month
(Before Last Reset). Only Import Demand is provided for kW Total, kvar total and kVA Total. Predicted
Demand is typically used for pre-alarming and to help users reduce power consumption using a Setpoint
to warn that the Demand limit may be exceeded
.
The PMC-53A-E provides the following setup parameters:
Setup Parameter
Definition
Options
Demand Period
(Register: 6029)
1 to 60 minutes. For example, if the # of Sliding Windows
is set as 1 and the Demand Period is 15, the demand cycle
will be 1×15=15min.
1 to 60 min
Default=15
# of Sliding Windows
(Register: 6030)
Number of Sliding Windows.
1 to 15
Default=1
Self-Read Time
(Register: 6033)
The Self-Read Time allows the user to specify the time
and day of the month for the Peak Demand Self-Read
operation. The Self-Read Time supports three options:
A zero value means that the Self-Read will take place at
00:00 of the first day of each month.
A non-zero value means that the Self-Read will take
place at a specific time and day based on the formula:
Self-Read Time = Day * 100 + Hour where 0 ≤ Hour ≤ 23
and 1 ≤ Day ≤ 28. For example, the value 1512 means
that the Self-Read will take place at 12:00pm on the
15th day of each month.
A 0xFFFF value will disable the Self-Read operation and
replace it with manual operation. A manual reset will
cause the Max. Demand of This Month to be
transferred to the Max. Demand of Last Month and
then reset. The terms This Month and Last Month will
become Since Last Reset and Before Last Reset.
Default=0xFFFF
Predicted Response
The Predicated Response shows the speed of the
70 to 99
