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IEC09000636 V1 EN
Figure 65:
Directional characteristic of the phase overcurrent protection
1 RCA = Relay characteristic angle 55°
2 ROA = Relay operating angle 80°
3 Reverse
4 Forward
If no blockings are given the start signals will start the timers of the step. The time
characteristic for step 1 and 4 can be chosen as definite time delay or inverse time
characteristic. Step 2 and 3 are always definite time delayed. A wide range of
standardized inverse time characteristics is available. The possibilities for inverse
time characteristics are described in section
"Inverse time characteristics"
.
All four steps in OC4PTOC can be blocked from the binary input BLOCK. The binary
input BLKSTx (x=1, 2, 3 or 4) blocks the operation of respective step.
Section 8
1MRK 504 135-UEN A
Current protection
150
Technical manual
Summary of Contents for ret650
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