sepam 20 user manual - Schneider Electric

2
Metering functions Phase current
Residual current
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Phase current
Operation
This function gives the RMS value of the phase currents:
b I1: phase 1 current
b I2: phase 2 current
b I3: phase 3 current.
It is based on RMS current measurement and takes into account harmonics up to
number 17.
Readout
The measurements may be accessed via:
b the display of a Sepam with advanced UMI by pressing the key
b the display of a PC with the SFT2841 software
b the communication link
b an analog converter with the MSA141 option.
Characteristics
Measurement range 0.1 to 1.5 In (1)
Unit A or kA
Accuracy typically ±1 % (2)
±2 % from 0.3 to 1.5 In
±5 % if < 0.3 In
Display format (3) 3 significant digits
Resolution 0.1 A or 1 digit
Refresh interval 1 second (typical)
(1) In rated current set in the general settings.
(2) At In, in reference conditions (IEC 60255-6).
(3) Display of values: 0.02 to 40 In.
Residual current
Operation
This operation gives the RMS value of the residual current I0.
It is based on measurement of the fundamental component.
Readout
The measurements may be accessed via:
b the display of a Sepam with advanced UMI by pressing the key
b the display of a PC with the SFT2841 software
b the communication link
b an analog converter with the MSA141 option.
Characteristics
Measurement range
Connection to 3 phase CT: 0.1 to 1.5 In0 (1)
Connection to 1 CT 0.1 to 1.5 In0 (1)
Connection to core balance CT with ACE990 0.1 to 1.5 In0 (1)
Connection to CSH residual
current sensor
2 A rating 0.2 to 3 A
20 A rating 2 to 30 A
Unit
Accuracy
A or kA
(2) typically ±1 % at In0
±2 % from 0.3 to 1.5 In0
±5 % if < 0.3 In0
Display format 3 significant digits
Resolution 0.1 A or 1 digit
(1) In0 rated current set in the general settings.
(2) in reference conditions (IEC 60255-6), excluding sensor accuracy.
PCRED301005EN - 06/2008