A fault is an unwanted connection, often to ground, that lets far too much current flow. Left alone it damages equipment and starts fires, so the grid is built to sense a fault and cut it off in a fraction of a second.
The devices that do this sit along the feeder. A fuse melts and opens for a fault below it. A recloser is smarter. Because most overhead faults are temporary, such as a branch that swings away or a bird that flies off, the recloser opens and then closes again to see whether the trouble has passed. It will try a set number of times.
If the fault is still there after the last try, the recloser locks out and leaves that section dark on purpose. That isolates the damage to the smallest possible piece of the system while the rest stays on.
Because most overhead faults are temporary, a recloser trips and recloses a set number of times -- here three -- testing whether the fault cleared. Only a fault that survives every try drives it to lock out and leave the section dark.
How a utility builds and protects its distribution grid sets the baseline for every equipment order that follows. The Feeder tracks the infrastructure investment and modernization programs reshaping that baseline, free, every week.
Question 1 of 2
A tree branch brushes a feeder and causes a brief fault. What does a recloser do first?
Educational material only. This is not engineering, safety, or procurement
advice. Confirm any value against manufacturer documentation and a licensed
professional before specifying equipment.