ABB RED650 Technical Manual page 257

1MRK 505 394-UEN A
Line differential protection RED650 2.2 IEC
Technical manual
U
a
a>b
U1>
b
IEC10000100 V2 EN-US
Figure 115: Logic diagram for step 1, definite time delay, DT operation
U1>
START
TRIP
tReset1
t1
IEC10000037 V2 EN-US
Figure 116: Example for step 1, Definite Time Delay stage 1 reset
tReset1 t1
t t
OFF ON
Delay Delay
Section 9
Voltage protection
ST1
TR1
AND
IEC10000100-2-en.vsd
IEC10000037-2-en.vsd
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