Protection Function Inputs And Outputs; C.t./V.t. Inputs - ABB REG316 4 Series Operating Instructions Manual

ABB Switzerland Ltd
3.2.

Protection function inputs and outputs

3.2.1.

C.t./v.t. inputs

(see Section 5.5.4.1.)
The protection scheme can include three types of input trans-
formers which may also have different ratings:
protection c.t's
·
metering c.t's (core-balance)
·
v.t's.
·
The number and arrangement of the input transformers are de-
fined by the value given for configuration code K.. or by entering
K=0 and specifying the required input transformer.
Before being processed by the protection functions, the currents
and voltages coming from the input transformers are digitised in
the analogue section of the main processor module.
Every analogue input channel is defined as being either single or
three-phase:
C.t's:
·
· three-phase protection
· single-phase protection
· single-phase metering (core-balance)
V.t's:
·
· three-phase Y connected
· single-phase.
A protection function can only be used in a three-phase mode, if
a corresponding three-phase group of c.t./v.t. input channels is
available.
All protection function settings are based on the REG 316*4
input values (secondary ratings). The fine adjustment to suit the
effective primary system quantities is accomplished by varying
the reference settings of the analogue inputs.
3-10
REG 316*4 1MRB520049-Uen / Rev. F