Sel 751A - Frequency Protection; Frequency Elements; Table 4.22 Frequency Settings; Figure 4.26 Loss-Of-Potential (LOP) Logic

4.47
Date Code 20100129 Instruction Manual SEL-751A Relay
Protection and Logic Functions
Frequency Protection
Figure 4.26 Loss-of-Potential (LOP) Logic
Frequency Protection
Frequency Elements
60
S
R
Q
Q
0
0
60
1
0
LOP
| V1 | > 5 V
Δ| V1 | > 20%
∆∠ I1 > 10°
| I1 |> 0.1 • I
NOM
∆∠ I2 > 10°
| I2 | > 0.1 • I
NOM
∆∠ I0 > 10°
| I0 | > 0.1 • I
NOM
| V2 | < 5 V
| V0 | < 5 V
| V1 | >
0.75 • VNOM
(RESET has priority)
Note: I
NOM
is 1 A or 5 A depending on the part number.
I
NOM
is the phase secondary input rating. VNOM is a relay setting.
Timer PU and DO times
are in cycles.
Relay
Word
Bit
∆ I1 > 0.1 • I
NOM
∆ I2 > 0.1 • I
NOM
∆ I0 > 0.1 • I
NOM
3
Table 4.22 Frequency Settings
Setting Prompt Setting Range
Setting Name :=
Factory Defau lt
FREQ1 TRIP LEVEL OFF, 20.00–70.00 Hz 81D1TP := OFF
FREQ1 TRIP DELAY 0.00–240.00 81D1TD := 1.00
FREQ2 TRIP LEVEL OFF, 20.00–70.00 Hz 81D2TP := OFF
FREQ2 TRIP DELAY 0.00–240.00 81D2TD := 1.00
FREQ3 TRIP LEVEL OFF, 20.00–70.00 Hz 81D3TP := OFF
FREQ3 TRIP DELAY 0.00–240.00 81D3TD := 1.00
FREQ4 TRIP LEVEL OFF, 20.00–70.00 Hz 81D4TP := OFF
FREQ4 TRIP DELAY 0.00–240.00 81D4TD := 1.00
FREQ5 TRIP LEVEL OFF, 20.00–70.00 Hz 81D5TP := OFF
FREQ5 TRIP DELAY 0.00–240.00 81D5TD := 1.00
FREQ6 TRIP LEVEL OFF, 20.00–70.00 Hz 81D6TP := OFF
FREQ6 TRIP DELAY 0.00–240.00 81D6TD := 1.00