3.3.2
Selection of a WIC1-Compatible Current Transformer
DANGER!
The terminal block for connection to the current transformers is not a shorting block.
Therefore always short-circuit current transformers before loosening the terminals.
Ignoring this can result in dangerous voltages at the open contacts (up to dozens of
kilovolts depending on the CT type).
DANGER!
The WIC1-compatible current transformers are dimensioned for nominal voltages
< 1000 V. This means for an application in MV-switchboards (i. e. voltages < 36 kV)
that these current transformers may only be used with insulated primary conductors,
for example cables, with appropriate insulation resistance against earth. These current
transformers are not allowed to be used for non-insulated primary conductors > 1000 V
against ground (earth).
In addition, the medium voltage cables, whose phase currents shall be measured via the
CTs, must be furnished with a grounded/earthed shielding.
Ignoring this can result in dangerous voltages at the open contacts (up to dozens of
kilovolts depending on the CT type).
For the test winding, see the Commissioning chapter, in particular ╚═▷ “7.1.4.1 Test
Windings, Test Sockets”.
68 WIC1 WIC1-1.0-EN-MAN
3 Hardware
3.3.2 Selection of a WIC1-Compatible Current Transformer