We recently carried out an electrical thermal imaging survey within a tower block in the financial centre of London. The client was a major stockbroker and the dealing floor electrical supplies are critical to the business. Our survey was carried out while supplies are on and circuits are under load.
While it is nice for us to identify and pick up numerous faults when conducting these surveys, sometimes there are no faults to report (good for the client) and sometimes there is just one.
On this occasion we identified an early stage fault developing on an isolator within the main switchboard which fed a distribution board.
A high resistance connection was identified on the outgoing phase 3 connection from the isolator. Current measurements on each phase were taken by our Thermographer who has a strong electrical background with readings of Phase 1 (46 Amps), Phase 2 (49 Amps) and Phase 3 (48 Amps). This confirms that the temperature rise was not related to an imbalanced load.
The presence of a thermal gradient (temperature reduces as you move away from the connection) on the cable was also a clear indication of a high resistance or loose connection.
The fault was reported to the client along with details of the severity and the remedial work required to rectify the problem.
If the fault had not been identified and allowed to develop further, then a potential fire, arc flash or loss of supply could have occurred to the distribution board. This would have directly affected a number of dealers desks and the cost to the client would have been significant.
Electrical thermographic surveys are carried out without interruption to supplies and are regarded as the best method of identifying potential faults on electrical systems.
Contact us for your free quotation.