Annual infrared scans of electrical equipment are required by NFPA 70B, 18-17.5.
Throughout this FIST volume, infrared (IR) scanning is recommended as a regular
maintenance procedure. Infrared scanning and analysis have become an
essential diagnostic tool throughout all industries and have been used in
Reclamation to detect many serious conditions requiring immediate corrective
action. Several forced outages have already been avoided. Infrared scanning is
non-intrusive and is accomplished while equipment is in service. It can be used
not only for electrical equipment but also to detect mechanical and structural
problems. Therefore, infrared scanning is HIGHLY recommended as a regularly
scheduled maintenance procedure.
Effective infrared scanning and analysis require the following:
The scanning equipment (IR camera and accessories) must be high quality and
correctly maintained and calibrated.
The IR camera operator must be trained to use the equipment and deal with
complicating issues such as differing emissivities of surfaces and reflectivity.
Certified Level 1 Thermographer (e.g., Academy of IR Thermography)
credentials, or higher, is recommended.
The IR system operator must be able to analyze results using state-of-the-art
software critical to successful interpretation of problems.
Field offices with adequate resources may find it possible to achieve professional
results by operating a local IR program. Others may find it more cost effective to
use the resources in the Hydroelectric Research and Technical Services Group
(D-8450). Call 303-445-2300 for more information.
At the time of the first publication of this FIST Volume 4-1B, a new FIST volume
defining the Reclamation infrared program is being developed which will assist
maintenance staff in conducting an infrared maintenance program.
Electrical power systems change as new generation and transmission lines are
added or modified. This may mean that equipment ratings are no longer
adequate. Underrated or misapplied electrical equipment can be hazardous to
personnel, to the integrity of the powerplant and power system, and to the
equipment itself. Therefore, it is necessary to periodically conduct fault and load
studies and to review equipment ratings (continuous current, momentary current,
momentary voltage, interrupting current, etc.) to ensure safe and reliable
operation. Requirements for reviewing equipment ratings are indicated where
appropriate in the maintenance schedules in this volume.