Field experience with multigas on-line monitoring of power transformers

Dissolved-gas analysis has long been recognized as the best method for the detection and identification of incipient faults in power transformers. This diagnostic method has progressed one step further with the introduction of the TNU on-line multigas monitor. Field demonstration has been in progress since June 1997 on a critical transformer of the Manitoba Hydro power system. On-line multigas monitoring has allowed control over the fault evolution. Transformer life has been extended more than one year, under safe conditions, in spite of a severe fault.