Name
Description
Range
Step
Default
df/dt>/< (1…8)
used in setting
group
Enables the protection stage in setting group.
0: No
1: Yes
-
0: No
df/dt>/< (1…8)
operating mode
Defines the operation mode of the protection stage. In "Rising"
mode df/dt function can trip only from increasing frequency. In
"Falling" mode df/dt function can trip only from decreasing
frequency. "Both" allows df/dt to trip from both.
0: Rising
1: Falling
2: Both
-
0: Rising
df/dt>/< (1…8)
frequency limit
Displays if frequency limits are used or not.
0: Not used
1: Use f limit
-
0: Not
used
df/dt>/< (1…8)
pick-up
Pick-up setting.
0.01…10.00Hz/s
0.01Hz/
s
0.2Hz/s
df/dt>/< (1…8)
f< limit
Underfrequency limit. Tripping is permitted when measured
frequency is under this value. This parameter is visible only when
operation mode is set to "Falling" or "Both".
7.00…65.00Hz/s
0.01Hz/
s
49.95Hz/
s
df/dt>/< (1…8)
f> limit
Overfrequency limit. Tripping is permitted if measured frequency
is above this value. This parameter is visible only when operation
mode is set to "Rising" or "Both".
10.00…70.00Hz/s 0.01Hz/
s
51Hz/s
df/dt>/< (1…8)
operating time
Operation time delay.
0.000...1800.000s 0.005s
0.1s
The pick-up activation of the function is not directly equal to the START signal generation of the
function. The START signal is allowed if the blocking condition is not active.
Operating time characteristics for trip and reset
This function supports definite time delay (DT). For detailed information on this delay types please refer
to the chapter "General properties of a protection function" and its section "Operating time
characteristics for trip and reset".
Read-only parameters
The relay's
Info page displays useful, real-time information on the state of the protection function. It is
accessed either through the relay's HMI display, or through the setting tool software when it is
connected to the relay and its Live Edit mode is active.
Table. 5.3.8 - 68. Information displayed by the function.
Name
Range
Step
Description
Measured df/dt
0.000...20.000Hz/s
0.001Hz/
s
Rate-of-change-of-frequency at the moment.
df/dt >/<
(1...8) condition
0: Normal
1: Start
2: Trip
3: Blocked
-
Displays the status of the protection function.
df/dt >/< (1...8)
df/dt meas / df/dt
set
0.000...20.000p.u.
0.005p.u. The ratio between the rate-of-change-of-frequency and the pick-up
value.
Expected
operating time
0.000...1800.000s
0.005s
Displays the expected operating time when a fault occurs.
Time remaining
to trip
-1800.000...1800.000s 0.005s
When the function has detected a fault and counts down time
towards a trip, this displays how much time is left before tripping
occurs.
A
AQ
Q-V211
-V211
Instruction manual
Version: 2.04
129