Download 3 - Schneider Electric

Metering functions
Peak demand active
and reactive power
Power factor (cos ϕ)
Peak demand active and reactive power
Operation
This function gives the greatest demand active or reactive power value since the last
reset.
The values are refreshed after each "integration interval", an interval that may be set
from 5 to 60 min (common interval with peak demand phase currents). The values
are saved in the event of a power failure.
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Readout
The measurements may be accessed via:
b the Sepam display via the
key
b the display of a PC with the SFT2841 software
b the communication link.
Resetting to zero
b via the clear key on the Sepam display if a peak demand is displayed
b via the clear command in the SFT2841 software
b via the communication link (remote control order TC5).
Characteristics
Demand active power
Demand reactive power
Measurement range
±(1.5 % Sn at 999 MW) (1)
±(1.5 % Sn at 999 Mvar) (1)
Units
kW, MW
kvar, Mvar
Resolution
0.1 kW
0.1 kvar
±1 % typical (3)
Accuracy
±1 %, typical (2)
Display format
3 significant digits
3 significant digits
Integration period
5, 10, 15, 30, 60 min
5, 10, 15, 30, 60 min
(1) Sn = 3Unp.In.
(2) At In, Unp, cos ϕ > 0.8 under reference conditions (IEC 60255-6).
(3) At In, Unp, cos ϕ < 0.6 under reference conditions (IEC 60255-6).
TS/TC equivalence for each protocol
Modbus
DNP3
IEC 60870-5-103
IEC 61850
TC
Binary Output
ASDU, FUN, INF
LN.DO.DA
BO14
-
MSTA1.RsMaxPwr.ctlVal
TC5
Power factor (cos ϕ)
MT10257
Operation
The power factor is defined by: cos ϕ = P ⁄
P2 + Q2 .
MT10258
It expresses the phase displacement between the phase currents and phase-toneutral voltages.
The + and - signs and IND (inductive) and CAP (capacitive) indications give the
direction of power flow and the type of load.
Readout
The measurements may be accessed via:
b the Sepam display via the
key
b the display of a PC with the SFT2841 software
b the communication link.
Characteristics
CEI Convention.
SEPED303001EN - 01/2013
Measurement range
-1 at 1 IND/CAP
Resolution
0.01
0.01 typical
Accuracy (1)
Display format
3 significant digits
Refresh interval
1 second (typical)
(1) At In, Unp, cos ϕ > 0.8 under reference conditions (IEC 60255-6).
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