Examples On How To Connect A Three Phase-To-Ground Connected Vt To The Ied - ABB REB670 Applications Manual

1MRK 505 337-UUS -
4.2.3.3
Application manual
+ +
V V
Pri Sec
a)
ANSI11000175 V1 EN
Figure 27: Commonly used markings of VT terminals
Where:
a) is the symbol and terminal marking used in this document. Terminals marked with a square
indicate the primary and secondary winding terminals with the same (positive) polarity
b) is the equivalent symbol and terminal marking used by IEC (ANSI) standard for phase-to-ground
connected VTs
c) is the equivalent symbol and terminal marking used by IEC (ANSI) standard for open delta
connected VTs
d) is the equivalent symbol and terminal marking used by IEC (ANSI) standard for phase-to-phase
connected VTs
It shall be noted that depending on national standard and utility practices the rated
secondary voltage of a VT has typically one of the following values:
• 100 V
• 110 V
• 115 V
• 120 V
• 230 V
The IED fully supports all of these values and most of them will be shown in the following
examples.
Examples on how to connect a three phase-to-ground connected VT to the
IED
Figure 28 gives an example on how to connect the three phase-to-ground connected VT
to the IED. It as well gives overview of required actions by the user in order to make this
measurement available to the built-in protection and control functions within the IED.
a
A
A
(X1)
(H1)
(H1)
N n N
(H2) (X2) (H2)
b)
Section 4
Analog inputs
da
A
(X1)
(H1)
dn
B
(X2) (H2)
c) d)
ANSI11000175_1_en.vsd
a
(X1)
b
(X2)
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