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Calcimator

Reliability Indices Calculator

Calculate SAIDI, SAIFI, and CAIDI from outage data.

Inputs

cust-hrs

Results

SAIFI

1.2 int/cust

SAIDI

2 hrs/cust

CAIDI1.67 hrs/int
ASAI99.98%
Total Outages150
Maifi0
How to Use This Calculator
  1. Enter Total Customers Served, Customer Interruptions, and Total Customer-Hours.
  2. Set Number of Outages and Major Event Days.
  3. Review SAIFI (int/cust) and SAIDI (hrs/cust).
  4. Use CAIDI (hrs/int) and ASAI (%) to inform your decision.

How the result changes with Total Customers Served

Total Customers ServedSAIFISAIDI
1,000,0900.12 int/cust0.2 hrs/cust
3,500,0650.03 int/cust0.06 hrs/cust
6,500,0350.02 int/cust0.03 hrs/cust
9,000,0100.01 int/cust0.02 hrs/cust

What each input means

Total Customers Served
Total number of customers in the service area.
Customer Interruptions
Total customer interruption events in the period.
Total Customer-Hours
Sum of all customer interruption durations in hours.
Number of Outages
Total number of distinct outage events.
Major Event Days
Number of days classified as major events (storms, etc.).

What each result means

SAIFI
System Average Interruption Frequency Index
SAIDI
System Average Interruption Duration Index
CAIDI
Customer Average Interruption Duration Index
ASAI
Average Service Availability Index

How this is calculated

Worked example, using the default values

  1. Identify Input Parameters
    4 parameters
    Total Customers Served = 100000, Customer Interruptions = 120000, Total Customer-Hours = 200000, Number of Outages = 150 = 5 input(s) provided
  2. Calculate SAIFI
    SAIFI
    1.2 = 1.2
  3. Calculate SAIDI
    SAIDI
    2 = 2
  4. Calculate CAIDI
    CAIDI
    1.67 = 1.67
  5. Calculate ASAI
    ASAI
    99.9772 = 99.9772

Engine last updated . Checked against 2 independently-derived tests — how we verify calculators.

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