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IEC09000636 V2 EN-US
Figure 73: Directional function characteristic
1. RCA = Relay characteristic angle
2. ROA = Relay operating angle
3. Reverse
4. Forward
8.2.3.1  Settings for each step
M12982-19 v10
x means step 1, 2, 3 and 4.
DirModex: The directional mode of step x. Possible settings are Off/Non-
directional/Forward/Reverse.
Characteristx: Selection of time characteristic for step x. Definite time delay and
different types of inverse time characteristics are available according to Table 
15.
1MRK 505 393-UEN B Section 8
Current protection
Line differential protection RED650 2.2 IEC 155
Application manual