Advertisement
RCD logic
(i)
Figure 2.19-7 illustrates the FRQ1 blocking by (1) RCD, Time derivative of frequency (Δf/Δt)
and (2) RCD-AR, active range selection. The user should have settings [FRQ-RCD] and [FRQ-
RCD-AR-OF/UF].
8700001C23
FRQBLK
1
(UVBLK)
&
-R
FRQ
-RCD
-D
&
&
OF
FRQ
-RCD-
AR
UF
&
FRQ-RCD-EN
Frequency(Hz)
f0 + 1.5
f0 + 1.0
f0 + 0.5
Nominal (f0)
f0 – 0.5
f0 – 1.0
f0 – 1.5
f0 – 2.0
f0 – 2.5
0
0.2
0.4
Figure 2.19-8 Active rage set with [FRQ-RCD-AR-OF/UF] settings
(1) RCD:
RCD element (Δf/Δt) is to monitor the change ratio of the frequency to the
time; the detection is regulated with setting [FRQ-RCD] (Hz/s). If the
frequency (f0) is changed rapidly rather than the [FRQ-RCD], 'FRQ-RC'
signal will be generated. The 'FRQ-RC' signal will be generated for both
raising and downing.
(2)RCD-AR: Settings [FRQ-RCD-AR-OF] and [FRQ-RCD-AR-UF] is to determine the
active range (Hz). 'FRQ-RC' signal is outputted upon the occurrence of rapid
Trip-block logic
8000211C2C
8000221C23
S
≥1
R
8100211C2D
8000211C2E
8000221C27
≥1
1
8100211C2F
On
Figure 2.19-7 Block for FRQ1 tripping
0.6
0.8
1.0
- 212 -
8200211B23
FRQ-RC
&
PLC programming
1.2
1.4
1.6
1.8
6F2T0207 (0.01)
800001EBB0 FRQ1-BLOCK
Setting[FRQ-RCD-AR-OF]
Setting[FRQ-RCD-AR-UF]
Time (sec)
2.0
GRE200 (5,6)
Advertisement
