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Picture 8. Characteristics of IDMTL
IDMTL (shown on picture 8) is a method to select a degree of slope under long time delay range.
IDMTL is used to improve breaker’s discrimination ability under overload protecting area. Not only long time delay
characteristic curve’s trip threshold can be changed but also degree of slope can be adjusted during its time delay
area. It is convenient to set up discrimination with high voltage protective devices (especially fuse) at steep slopes.
IDMTL (Inverse Definite Minimum Time Lag)
Protective Coordination
2. Selectivity Techniques