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CET Inc.
4.2 Power, Energy and Demand
4.2.1 Basic Measurements
The PMC-512-D provides the following basic measurements that can be accessed via the communication:
Parameter
Description
Mains Current Type = Incomer
Mains Current Type = Residual
U
Mains Voltage
●
●
I
Mains Current
●
○
Ir
Residual Current
○
●
%Loading
Mains Loading rate
●
○
P
Mains Power
●
○
kWh
Mains Energy
●
○
I1-I12
SM1-12 Current
●
●
%Loading1-12
SM1-12 %Loading
●
●
P1-P12
SM1-12 Power
●
●
kWh1-12
SM1-12 Energy
●
●
AI
Analog Input
●
●
Table 4-4 Basic Measurements
4.2.2 Energy Measurements
The PMC-512-D's Energy measurements include Mains Energy (if the
Mains Current Type
=
Incomer
)
and SM 1-12 Energy at a resolution of 0.01kWh and a maximum value of 999,999.99kWh. When the
maximum value is reached, it will automatically roll over to zero.
The energy can be reset manually via the Front Panel or through communications.
4.2.3 Demands
Demand is defined as the average power consumption over a fixed interval (usually 15 minutes) based
on the sliding window method. The PMC-512-D provides the Current and kW Total Present Demand of
Mains and Branch Circuits as well as the Current and kW total Peak Demand of Mains and Branch Circuits
for
This Month (Since Last Reset)
and
Last Month (Before Last Reset)
. Please note that the kW total
Present and Peak Demand for the Mains Circuit are not available if the
Mains Current Type
is
Residual
Current
. The Present Demand and Peak Demand data can be retrieved via Communications and, its Setup
Parameters are available via the Front Panel and through communications.
The PMC-512-D provides the following Demand setup parameters:
Parameter
Definition
Options
Demand Period
(Reg. # 6006)
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 minutes
Default=15
# of Sliding
Windows
(Reg. # 6007)
Number of Sliding Windows.
1 to 15
Default=1
Self-Read Time
(Reg. # 6008)
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 x 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
Default=0xFFFF