Thermal imaging, using portable thermal cameras, of electrical switchboards has been used for decades now as a condition maintenance tool, but has it outlived its usefulness?
Well, probably! Opening doors and/or removing Perspex panels exposes the thermographer to significant risk from arc flash and a possible agonising death from burns.
‘Popping’ the safety device on isolators and main switches so panels can be opened for thermal imaging with the supply on, is in direct contradiction of Work Health and Safety legislation and again exposes the thermographer to the arc flash risk.
Insurance companies have prompted thermal imaging of electrical switchboards in many cases in the past but could now expose themselves to legal action should something happen if they haven’t covered off on their ‘duty of care’.
The dangers presented by the arc flash risk when opening panels may outweigh the benefits gained from thermography when there are now new ways to design out the risk.
Arc contained windows can be used by thermographers to view busbars and connections but they do have a limited angle and view. Permanent cameras can be mounted to ‘view’ critical connections. Busbar temperature sensors can be used from permanent temperature monitoring.
Additionally, ultrasonic and acoustic detectors could be used to detect arcing in switchboards and portable or permanently installed partial discharge detectors can be used for medium voltage switchboards to detect pending failure of insulation.
Thermography of outdoor substation and poles and wires still present an excellent opportunity to carry out condition monitoring to prevent incidents and outages.
