IDMT (Inverse Definite Minimum Time) Relay Calculation

IDMT (Inverse Definite Minimum Time) Relay Calculation

Overcurrent and Earth Fault Relay Setting

Setting calculation is separated for overcurrent and eart fault relay. For both settings, there are few following input parameters:

  1. Name of Feeder
  2. Load Current: (IL) in Amps
  3. Min Fault Current (Line-Line) in Amps
  4. Max Fault Current (Line-Line) in Amps
  5. Relay Type
  6. Relay Code
  7. Relay No
  8. CT Primary Current (in Amps)
  9. CT Secondary Current (in Amps)
  10. Relay Error (%)
  11. CT Error (%)
  12. Over shoot (in seconds)
  13. C.B Interrupting Time (in seconds)
  14. Safety (in seconds)

Summary of overcurrent and earth fault relay settings:

  1. Actual Plug (Relay Pick up) setting
  2. Plug Setting Multiplier (PSM)
  3. Time setting
  4. Total Grading Time
  5. Low Over Current Setting: (I>)
  6. Actual Operating Time of Relay (tI>)
  7. High Over Current Setting: (I>>)
  8. Actual Operating Time of Relay (tI>>)
Software:IDMT (Inverse Definite Minimum Time) Relay Calculation
Developer:Jignesh Parmar
Size:39.1 Kb
Download:Right here

IDMT (Inverse Definite Minimum Time) Relay Calculation

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Page edited by E.C. (Google).


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