ABB
Transformer Protection and Control
RET615
Product version: 2.0
Measurement functions
Table 43. Three-phase current measurement (CMMXU)
Characteristic
Operation accuracy
Suppression of harmonics
Table 44. Residual current measurement (RESCMMXU)
Characteristic
Operation accuracy
Suppression of harmonics
Value
Depending on the frequency of the current
measured: f
±2Hz
n
±0.5% or ±0.002 x I
n
(at currents in the range of 0.01...4.00 x I
DFT: -50dB at f = n x f
n
...
RMS: No suppression
Value
Depending on the frequency of the current
measured: f/f
= ±2Hz
n
±0.5% or ±0.002 x I
n
at currents in the range of 0.01...4.00 x I
DFT: -50dB at f = n x f
n
...
RMS: No suppression
1MRS756891 B
Issued: 01.10.2009
)
n
, where n = 2, 3, 4, 5,
n
, where n = 2, 3, 4, 5,
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