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10,000+
km HT Lines
SAIDI & SAIFI
200+
Projects Completed
20+
Years Experience
What Do SAIDI & SAIFI Actually Mean?
Think of them as the grid's report card. Utilities, regulators, and engineers track these two numbers to measure how well a power network serves its customers.
SAIFI
System Average Interruption Frequency Index
Formula
Total Customer Interruptions ÷ Total Customers Served
Example: If a utility with 500,000 customers records 1,200,000 interruption events in a year — SAIFI = 2.4 outages per customer per year.
SAIDI
System Average Interruption Duration Index
"How many total minutes per year does the average customer sit without power?"
Formula
Total Customer Outage Minutes ÷ Total Customers Served
Example: 72,000,000 outage-minutes across 500,000 customers — SAIDI = 144 minutes (~2.4 hrs) per customer per year.
CAIDI
Customer Average Interruption Duration Index
The third pillar — CAIDI tells you how fast crews restore power once an outage happens. It measures restoration speed independent of frequency.
CAIDI = SAIDI ÷ SAIFI — measured in minutes per event
What Drives Outages — and How to Fix Them
Every SAIDI/SAIFI spike has a root cause. Identifying it is the first step to deploying the right technology.
Common Causes
Tree contact on overhead lines
Transformer or equipment failure
Lightning strikes
Storms, cyclones, ice loading
Animal contact (birds, rodents)
Aging cable insulation failure
Engineering Fixes
Auto Reclosers
SCADA-based fault location
FLISR automation (reroute in seconds)
Sectionalizers — isolate fault zones
Fault Passage Indicators
N-1 redundant transmission paths
Sugs Lloyd Products That Move These Numbers
Our products are engineered specifically to reduce SAIDI and SAIFI for distribution utilities across India and beyond.
Fault Passage Indicators
Pinpoint the exact location of a fault on the network, dramatically cutting the crew time needed to find and fix the problem — directly slashing SAIDI.
↓ SAIDI
Auto Reclosers
Automatically disconnect the faulted section and re-energise the healthy network within seconds. Prevents temporary faults from becoming sustained outages.
↓ SAIDI
↓ SAIFI
​Sectionalisers
SF6-insulated self-contained devices that isolate faulted feeder sections automatically, working in coordination with upstream reclosers to restore healthy zones instantly.
↓ SAIDI
Outage Management System
Our OMS platform gives operators a real-time view of outage events, affected customers, and restoration progress — enabling faster, smarter response decisions.
↓ SAIDI
↓ SAIFI
Distribution Automation System
Full FLISR capability — automatically faults are located, isolated, and healthy sections restored within seconds without human intervention. The fastest path to low SAIDI.
↓ SAIDI
↓ SAIFI
EPC Project Management
Full turnkey construction and upgrade of HT/LT lines and substations — the physical infrastructure backbone that all reliability improvements depend on.
↓ SAIDI
↓ SAIFI