Woodward HighPROtec MCDLV4, Руководство пользователя

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Protective Elements
About application type 2:
This application type has an additional transformer within the line, which is the primary protection object. The
reference current “Ib” is no longer any of the rated transformer currents, but the nominal current of the transformer
(which is calculated from the nominal apparent power and the nominal voltage of the winding side.
The phase differential protection (87T) uses the winding side W1 (primary side) as the reference, so that the
reference current “Ib” now equals the nominal current of the winding side W1 of the transformer.
For an earth differential current protection (87N, 64REF) the reference current “Ib” equals the nominal current of the
winding side to which this protection type is applied (winding W1 or W2).
For each of the two devices it must be selected via parameter [Field settings / Transformer / Measuring side] to
which winding side of the transformer the protective device is connected.
Example:
The winding side W1 (primary side) is monitored by the protective device at substation A, the winding side W2
(secondary side) is monitored by the protective device at substation B.
The following settings have to be done for the protective device at substation A:
[Field settings / Transformer / Measuring side
= W1]
The CT-related settings must be done the same way as described for application type 1 above.
The following settings have to be done for the protective device at substation B:
[Field settings / Transformer / Measuring side
= W2]
The CT-related settings must be done the same way as described for application type 1 above.
600 MCDLV4 DOK-HB-MCDLV4-2E