When the lights go out unexpectedly, everyone wants to know: what happened?
There are many causes of power outages, with weather and cable faults being, by far, the two most common.
So what exactly is a "cable fault"? We asked Cableman Jeff.
What's a cable fault?
A cable fault is when the insulation of a power cable deteriorates enough that it's no longer able to contain the voltage, causing a short.
Basically, it's a hole, or a crack, burning through the cable.
Check out what a cable fault looks like. Click on the images above.
What causes a cable fault?
- Moisture, grit and/or contamination make a crack in the cable insulation, and the crack gradually grows close enough to the core to create a short.
- Normal aging
- Accelerated aging (e.g. due to environmental stresses), which may lead to issues such as overheating
- Corrosion of the cable-protected insulation
- Degradation of the cable insulation
- Third-party damage (e.g. someone damaging a cable during excavation work)
How do we find cable faults?
Faults are easily identifiable on aerial wires, but what about on cables buried three feet underground?
A two-man crew uses a special vehicle — the only one in the EPCOR fleet — called a fault locator truck (a.k.a. the "thumper truck") to pinpoint where a cable fault is underground.