Calculated Analogue Channels - ABB REC 523 Technical Reference Manual

REC 523
5.3.3.
32
Remote Monitoring and Control Unit
Technical Reference Manual
The correction parameters/factors are calculated as follows:
Current transformers
Amplitude error at current I
(e = error in per cent)
Amplitude error at current 0.01 x I
(e = error in per cent)
Phase displacement error at current I
(e = error in degrees)
Phase displacement error at current 0.01 x I
(e = error in degrees)
Voltage transformers
Amplitude error at voltage U
(e = error in per cent)
Phase displacement error at voltage U
(e = error in degrees)
Rogowski coil
Amplitude error for the entire measuring range
(e = error in per cent)
Phase displacement error for the entire measuring
range (e = error in degrees)
Voltage divider
Amplitude error for the entire measuring range
(e = error in per cent)
Phase displacement error for the entire measuring
range (e = error in degrees)

Calculated analogue channels

REC 523 includes virtual channels to obtain phase-to-phase voltages, residual
voltage and neutral current when sensors are used. Current sensors and voltage
dividers are connected to the feeder terminal via coaxial cables. Therefore a phase-
to-phase voltage connection, an open-delta connection of phase voltages or a
residual connection of phase currents cannot be made. Both the amplitude and the
phase angle are calculated for the virtual channels.
The virtual channel voltages and currents are numerically derived from the phase
voltages and phase currents according to Table 5.3.3-1. Though primarily meant to
be used with sensors, the calculated analogue channels can also be used with
conventional current and voltage transformers.
The virtual channels are numbered according to the priority numbers in the Table
5.3.3-1. The virtual channel used first is numbered as 11 and the following as 12, 13
and so on. For example, U
channels are selected for use.
Amplitude correction factor 1
n
= 1 / (1+ e/100)
Amplitude correction factor 2
n
= 1 / (1+ e/100)
Phase displacement error 1 = - e
n
Phase displacement error 2 = - e
n
Amplitude correction factor
n
= 1 / (1+ e/100)
Phase displacement error
n
= - e
Amplitude correction factor
= 1 / (1+ e/100)
Phase displacement error = - e
Amplitude correction factor
= 1 / (1+ e/100)
Phase displacement error = - e
is numbered as 11 and U
0s
1MRS750881-MUM
as 12, if these virtual
12s