What does the IDMT means, which is available only in 6.0P not in 6.0E ?
The IDMTL ( Inverse definite Minimum Time lag) curves for long time protection against overloads for Micrologic P and H are used to improve the discrimination with fuses positioned upstream (HV) and/or downstream network. Normally , it has five types of curves:
1. DT : Definite Time
2. SIT : Standard Inverse Time
3. VIT : Very Inverse Time.
4. EIT : Extremely Inverse Time
5. HVF : High Voltage Fuse.
If the IDMTL Curve is selected , the protection for neutral is disabled but the short circuit protection remains operational.
IDMTL curves for micrologic complies with the IEC 60255 equations that gives prefered multipliers for all the curves used for micrologic P and H except for SIT curve where 0.5 is used instead of 0.02 due to the lack of CPU time and Memory . Please follow the link below for the Table data of Micrologic P (refer page4 and 21).