ASUI

The Average Service Unavailability Index (ASUI)^[1] is a reliability index commonly used by electric power utilities. It is calculated as

${\displaystyle {\mbox{ASUI}}={\frac {\sum {U_{i}N_{i}}}{\sum {N_{i}}\times 8760}}=1-{\mbox{ASAI}}}$

where $N_{i}$ is the number of customers and $U_{i}$ is the annual outage time (in hours) for location $i$. ASUI can be represented in relation to SAIDI (where annual SAIDI is given in hours) as

${\displaystyle {\mbox{ASUI}}={\frac {\mbox{SAIDI}}{8760}}}$

See also

• Average Service Availability Index (ASAI)
• ASIDI
• ASIFI
• ASUI
• CAIDI
• CAIFI
• CTAIDI
• MAIFI
• SAIDI
• SAIFI

References

1. Pham, Hoang (8 April 2003). Handbook of reliability engineering. Birkhäuser. p. 514. ISBN 978-1-85233-453-6. Retrieved 21 July 2011.