Underground Power Cable Fiber Optic Monitoring
Monitoring below-ground power cables is important for ensuring the safety and reliability the safety and reliability of the power distribution network. It typically involves using specialized equipment to detect and locate any faults or abnormalities in the cables. The most accurate and intelligent type of monitoring system uses Fiber Optic Cables that run along the power cables.
HAWK, a leading provider of underground power cable fiber optic monitoring, can assist you with all your needs. Contact us today to learn more about our praetorian sensing for underground power cable capabilities and above-ground power cable monitoring.
How it Works: Sensing Methods
HAWK's Fiber Optic Sensing System, the Praetorian, uses a combination of Distributed Acoustic Sensing (DAS) and Distributed Temperature Sensing (DTS) to protect underground buried assets. By exciting a fiber optic core within a cable the Praetorian Interrogator can utilize the fibers as a distributed network equivalent to up to 1.6 Million individual vibration, temperature, and strain sensors.
Because Praetorian utilizes a number of different sensing methods it is possible to observe events in several physically independent ways. Consequently, Praetorian is inherently resistant to taking a given reading and giving a false alarm due to the requirement for multiple physical effects to simultaneously occur at the same location to signify an event and trigger an alarm.
How it Works: Monitoring
Through a combination of distributed vibration, temperature, and strain monitoring, it is possible to determine multitudes of different physical events along a cable, including but not limited to:
- Detection of partial discharge
- Detection of hot spots
- Early alert of third-party intrusion (accidental or nefarious)
- Conductor break detection • Ground condition assessment
- Prevention of arc flash events from conductor contact
- Detection of optical loss
- Detection of fiber break
- Detection of pit or trench lid being opened
- Determination of network operational status (thermal loading)
- Praetorian also Geo-tags alarms allowing security or maintenance teams to be able to respond immediately
Frequently Asked Questions
Time of Flight. Locations of events are able to be accurately determined by a method called time of flight. The amount of time from sending the laser pulse to receiving a return signal is recorded. Due to the internal properties of a fiber optic core, the speed of light through a fiber is consistent at approximately two thirds of the speed of light through a vacuum (around 400μs for a 40km (25 miles) round trip). As this is consistent, the return time can be used to calculate a distance on the fiber.
Often the primary way of preventing damage to buried assets is to prevent them being struck and damage by third parties. As significant excavations are generally required to unearth buried assets due to their depth of cover the process of excavation takes sufficient time that a warning provided quickly enough can give an operator enough time to alert the third party to the dangers below them. Different digging events generate different signals which are picked up by the monitored fiber that are either part of or buried alongside the asset.
No, it requires no additional field infrastructure such as power or communications
Because Fiber Optic Technology provides a solution that is preventative rather then reactive