Distributed measurement of conductor temperatures in mine trailing cables using fiber-optic technology

Abstract

Mine trailing cables operated above safe thermal limits can cause premature insulation failure, increasing electrocution and fire hazards. Previous U.S. Bureau of Mines Pittsburgh Research Center research showed that, under static test conditions, electrical current levels permitted under present regulations may not limit cable temperatures to less than the 90 C rating of reeled trailing cable. Continuing research under the National Institute for Occupational Safety and Health (NIOSH) addresses thermal characteristics of reeled trailing cable under dynamic test conditions more representative of field conditions, where operators constantly reel in and pay out cable. This research is in support of efforts by industry associations and the Mine Safety and Health Administration to establish safety guidelines for cyclically rated reeled machines. This paper describes a unique approach to measuring temperatures within reeled cable under dynamic test conditions. Fiber-optic sensors embedded within the metallic conductors measure temperatures at 1-m intervals along the entire length of cable. Temperature measurements arereported to be accurate to within 61 C. The test setup requires access to only one end of the trailing cable, allowing researchers to freely reel in and pay out cable while temperature measurements are made, simulating field conditions. Manufacture of a fiberoptic-embedded trailing cable is described, along with initial test results that indicate the fiber-optic approach is viable.

Ladder-Type Soil Model for Dynamic Thermal Rating of Underground Power Cables

“…2 are calculated. Finally, with (10), the values for R si are obtained. The parameter values of the model (Fig.…”

Distributed Temperature Sensing: Review of Technology and Applications

“…For safe electrical operation, in mines, shuttle car trailing cables should be operated below the safety limit which is about 90 C [45]. Operation in temperature condition more than that might cause premature insulation failure.…”

“…Dubaniewicz et al [45] reported utilization of DTS systems embedded within the metallic conductors to measure temperatures at 1 m intervals along the entire cable length, at an accuracy of C. In addition to the distributed temperature, Dubaniewicz et al [46] also reported use of fiber optic technology to monitor atmospheric related parameters like methane (CH ) and carbon monoxide (CO).…”