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Figure 341: Example of definite time operation of IFPTOC, when Operation principle
= “EF current based”, Operating curve type = “Definite time”. Settings EF current Str
Val = 0.04*In (4A) and DT stage Op time = 400ms. Reduction factor = 1.0. Maximum
earthing Ris = 10ohm.
When
Operating curve type = “Inverse time EN50522” is selected, then
• Operate time is inverse time according to standard EN50522:
Protection functions
1MRS759142 F
600
REX640
Technical Manual