SAIDI is an abbreviation for System Average Interruption Duration Index. This index is commonly referred to as customer minutes of interruption, and is designed to provide information about the average time the customers are interrupted. This part of my report analyzed SESB Tawau SAIDI contributed from Tepekong Cina Substation for May 2009 focusing on breakdown due to blown fuse.

Data for the analysis was obtained from TCS and LGBnet. Calculation of SAIDI for Tepekong Cina Substation is shown below.

SAIDI = (Affected Consumer) (Interruption Duration)/
Total no of customer served
= 31693 / 41137
= 0.77 min

Total SAIDI for the month is 294.94 min which include SAIDI from distribution, transmission and generation side. If compared to the total SAIDI, the Tepekong Cina Substation only contributes 0.266%. If compared to distribution (33kV to 415V) SAIDI which are 32.07 min, the substation contribute 2.4%. LV breakdown SAIDI is 4.89 min with 15.75% contributed from the substation.

Although frequent interruption experienced by the substation, low percentage of SAIDI was contributed to the total SAIDI. It is due to small number of customer affected, but still the interruption duration can be as long as 274 minutes or 4 hours and 34 minutes as recorded in the LGBnet.