Application Guide - NP900 Series
472 (504
)
A996A
Table 3.7.2.2-277 Pick-up characteristics setting
Name
Range
Step
Default
Description
Voltage low
pickup
0.00 … 0.50 x Un
0.01 x Un 0.05 x Un If at least one of the measured voltages are
under this set value the function will pick up
Voltage high
detect
0.01 … 40.00 x In
0.01 x In
0.10 x In
If at least two of the measured voltages are
over this set value the function will pick up
Angle shift
limit
2.00 … 90.00 deg
0.10 deg
5.00 deg
If the difference between the angle in
present time and -40ms before is greater
than the set value function will pick up
Line Fuse
fail check
No
Yes
-
Yes
Selection if the state of the line fuse will be
supervised. The supervised signal is
determined in IO
Fuse-Failure Inputs
Bus Fuse fail
check
No
Yes
-
Yes
Selection if the state of the bus fuse will be
supervised. The supervised signal is
determined in IO
Fuse-Failure Inputs
The pick-up activation of the function is not directly equal to start-signal generation of the
function. Start signal is allowed if blocking condition is not active. From binary signals the
activation of the pick-up is immediate when the monitored signal is activated.
Voltage transformer supervision can also report several different states of the measured
voltage. These can be seen in the INFO-page of the function in the relay HMI or in
SMART9.
Name
Description
Bus dead
No voltages
Bus Live VTS Ok
All of the voltages are within the
set limits
Bus Live VTS Ok SEQ
Rev
All of the voltages are within the
set limits BUT the voltages are
in reversed sequence
Bus Live VTS Ok SEQ
Undef
Voltages are within the set limits
BUT sequence cannot be
defined.
Bus Live VTS problem
Any of the VTS pick-up
conditions are valid!
3.7.2.3
F
UNCTION BLOCKING
In the blocking element the block signal is checked in the beginning of each program
cycle. Blocking signal is received from the blocking matrix for the function dedicated input.
If the blocking signal is not activated when the pick-up element activates, a START signal
is generated and the function proceeds to the time characteristics calculation.
If blocking signal is active when pick-up element activates a BLOCKED signal will be
generated and the function shall not process the situation further. If START function has
been activated before blocking signal it will reset and the release time characteristics are
processed as in case of when pick-up signal is reset.
