Ice NP900 Series, Инструкция по применению

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Application Guide - NP900 Series 11 (504
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the used scaling factors can now be seen. Primary to secondary ratio is directly the ratio
of the set CT ratios, CT scaling factor to nominal is now the set CT primary to nominal
current ratio, per unit scalings to primary is changed now to nominal current and the
secondary per unit factor is calculated accordingly to the given ratio of CT primary to
object nominal current.
If coarse residual current (I01) is wanted to be used for CT sum input then it should be set
to phase current CT ratings 100/1A.
Figure 3.1.1.1-5 Residual current I01 scaling to summing connection.
For the sensitive residual current (I02) measurement is set directly 10/1A rated currents.
Figure 3.1.1.1-6 Residual current I02 scaling to ring core CT input.
If the scaling was made to CT primary or to object nominal current the measurements will
look as follows with nominal current feeding:
Figure 3.1.1.1-7 Scalings to CT nominal.