ABB Relion REG670, Technical Manual, Page: 533 / 1298

9.4.7.6 Logic diagram
IEC05000162-3-en.vsd
t
³
1
&
&
BLOCK
Xleak
Ei
M=
(Ei / f)
(Ur / fr)
M = relative V/Hz as service value
V/Hz>>
M>V/Hz>>
V/Hz>
M>V/Hz>
IEEE law
Tailor-made law
tMax
Calculation
of internal
induced
voltage Ei
k
M
M
tAlarm
ALARM
TRIP
AlarmLevel
U3P
I3P
t
t
tMin
&
IEC05000162 V3 EN
Figure 253: A simplified logic diagram of the Overexcitation protection
OEXPVPH
Simplification of the diagram is in the way the IEEE and Tailor-made delays are
calculated. The cooling process is not shown. It is not shown that voltage and
frequency are separately checked against their respective limit values.
9.4.8 Technical data
Table 290: OEXPVPH technical data
Function Range or value Accuracy
Operate value, start (100–180)% of (
UBase/f
rated
) ± 0.5% of U
Operate value, alarm (50–120)% of start level ± 0.5% of U
r
at U ≤ U
r
± 0.5% of U at U > U
r
Operate value, high level (100–200)% of (
UBase/f
rated
) ± 0.5% of U
Curve type IEEE or customer defined
2
(0.18 )
:
( 1)
k
IEEE t
M
×
=
-
EQUATION1319 V1 EN
(Equation 133)
where M = (E/f)/(Ur/fr)
± 5.0 % or ± 45 ms,
whichever is greater
Minimum time delay for inverse
function
(0.000–60.000) s ± 1.0% or ± 45 ms,
whichever is greater
Maximum time delay for inverse
function
(0.00–9000.00) s ± 1.0% or ± 45 ms,
whichever is greater
Alarm time delay (0.00–9000.00) ± 1.0% or ± 45 ms,
whichever is greater
1MRK502052-UEN B
Section 9
Voltage protection
527
Technical manual