
M-3410A Instruction Book
3–4
Nominal Frequency
This function allows the user to select the nominal
frequency of the M-3410A to match the power
system. Changes to Nominal Frequency will reset
the 81 Function setpoints to their default values.
Therefore, ensure that 81 Function setpoints are
properly set any time the Nominal Frequency is
changed.
CT Secondary Rating
This function allows the user to select the CT
Secondary Rating to match the M-3410A Application
(5 A or 1 A).
Nominal Voltage
The Nominal Voltage (V
nom
) is defined as the phase
voltage measured at relay terminals when the
generator/interconnection is at rated voltage (V
rated
).
When line-gnd or line-line selection is used, V
nom
=
V
rated
/VT
ratio
. When line-ground-to-line-line selection
is used, V
nom
=
S
3 x V
rated
/VT
Ratio
.
Nominal Current
The Nominal Current (
I
nom
) is defined as the secondary
CT current of the phase CT’s when the CT primary
current equal to the generator/interconnection rated
current (
I
rated
) is given by
I
nom
=
I
rated
/CTratio.
Input Active State
This designates the “active” or asserted state for
the individual status input:
•
Selected Closed causes the “active” or
“operated” condition to be initiated by the
external contact
closing.
•
Selecting Open causes the “active” or
“operated” condition to be initiated by the
external contact
opening.
Output Contact Mode
In the “normal” mode, when the condition for
assertion has been removed, the energized relay
coil will de-energize automatically after the
corresponding seal-in timers have expired. If the
seal-in timer has already expired, the output contact
will de-energize immediately.
If “latching” is selected, the output will stay
energized until manually reset from IPScom
®
or by
pressing the
TARGET/OUTPUT RESET
pushbutton.
The latch condition is maintained as long as power
is applied to the relay.
VT Configuration
Indicates VT connection. (See Figure 2-10 through
2-14) When line-ground voltages are used, functions
27, and 59 may operate for line-ground faults. If this
is not desired, the line-gnd-to-line-line selection
should be used to prevent operation of these
functions for line-ground faults.
When line-gnd-to-line-line is selected, the relay
internally calculates line-line voltages from
line-ground voltages for all voltage sensitive
functions. This line-gnd-to-line-line selection should
be used only for a VT nominal secondary voltage of
277 V or below. For this selection, the nominal
voltage setting entered should be line-line nominal
voltage, which is
S
3 times line-ground nominal
voltage.
When line-gnd or line-gnd-to-line-line selection is
used, functions 27G, 59G and 25 are not available.
When line-line selection is used, the 3rd input
voltage can be connected to neutral voltage (or
3V
0
) for 27G and 59G functions, or it can be used
for 25 function. Hence, when 27G and 59G are
used, 25 function is not available and vice versa.
Also, when line-line or line-gnd-to-line-line selection
is used, the 32 function can only be set to 3-phase
power measurement, and not single-phase.
59/27 Magnitude Select
This function allows the use of RMS (Root-Mean-
Squared) or DFT (Discrete Fourier Transform) derived
values for the 59 and 27 functions. The impact of
the selection:
•
RMS – provides RMS value of the total
waveform, including all harmonics.
•
DFT– provides the RMS value of the
fundamental waveform (50 or 60 Hz,
depending on system nominal frequency)
When the RMS option is selected, the resulting
calculation is accurate over a wide frequency range
(10 to 80 Hz), and the 27 or 59 element time
response can be slowed by up to 20 cycles. When
the DFT option is selected, the resulting calculation
is accurate near the fundamental frequency (50 or
60 Hz, depending on system nominal frequency),
and the element time response is accurate to
&
2
cycles. For generator protection purposes, the RMS
option is recommended. The factory default setting
for this option is RMS.
Phase Rotation
This function allows the user to select the phase
rotation of the M-3410A to match that of the power
system (ABC or ACB).
Содержание Syncrocloser M-3410A
Страница 1: ...Instruction Book M 3410A Intertie Generator Protection Relay ...
Страница 39: ...xiv M 3410A Instruction Book This Page Left Intentionally Blank ...
Страница 71: ...M 3410A Instruction Book 2 28 This Page Left Intentionally Blank ...
Страница 121: ...M 3410A Instruction Book 3 50 This Page Left Intentionally Blank ...
Страница 161: ...1 3 A B C M 3410A Instruction Book 4 40 This Page Left Intentionally Blank ...
Страница 223: ...M 3410A Instruction Book F 2 This Page Left Intentionally Blank ...