ABB RET615 - Page 47

Measurement functions
Table 55. Three-phase current measurement (CMMXU)
Characteristic Value
Operation accuracy Depending on the frequency of the current measured: f
n
±2 Hz
±0.5% or ±0.002 x I
n
(at currents in the range of 0.01...4.00 x I
n
)
Suppression of harmonics DFT: -50 dB at f = n x f
n
, where n = 2, 3, 4, 5,…
RMS: No suppression
Table 56. Three-phase voltage measurement (VMMXU)
Characteristic Value
Operation accuracy Depending on the frequency of the voltage measured: f
n
±2 Hz
At voltages in range 0.01…1.15 x U
n
±0.5% or ±0.002 x U
n
Suppression of harmonics DFT: -50 dB at f = n x f
n
, where n = 2, 3, 4, 5,…
RMS: No suppression
Table 57. Voltage sequence components (VSMSQI)
Characteristic
Value
Operation accuracy Depending on the frequency of the voltage measured: f
n
±2 Hz
At voltages in range 0.01…1.15 x U
n
±1.0% or ±0.002 x U
n
Suppression of harmonics DFT: -50 dB at f = n x f
n
, where n = 2, 3, 4, 5,…
Table 58. Residual current measurement (RESCMMXU)
Characteristic
Value
Operation accuracy Depending on the frequency of the current measured: f/f
n
= ±2 Hz
±0.5% or ±0.002 x I
n
at currents in the range of 0.01...4.00 x I
n
Suppression of harmonics DFT: -50 dB at f = n x f
n
, where n = 2, 3, 4, 5,…
RMS: No suppression
Transformer Protection and Control 1MRS756891 F
RET615
Product version: 4.0
ABB 47