skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Arc products of transformer insulating systems containing tetrachloroethylene. Final report

Technical Report ·
OSTI ID:6104397

A low current laboratory arc interruption cell was adapted to study the arc products of Wecosol (C/sub 2/Cl/sub 4/) and 75W% C/sub 2/Cl/sub 4/-25W% mineral oil-solid insulation systems for fire resistant transformers to determine the toxicity hazard of arc failures of these transformers. The use of the relatively low current (40 to 50 ampere) arcs was justified on the basis that their maximum temperature was above the chemical reaction temperatures just as in the case of kiloampere arc failures of transformers. Analytical methods were developed to determine arc products, principally for COCl/sub 2/ (phosgene). A relative hazard criterion is presented. The major arc products of the Wecosol systems are Cl/sub 2/, HCl, C/sub 2/Cl/sub 6/ (reaction of Cl/sub 2/ + C/sub 2/Cl/sub 4/) and CCl/sub 4/, and the minor products are COCl/sub 2/, CO and CO/sub 2/. The principal arc failure hazard here would be due to Cl/sub 2/ and HCl, and there is a low probability of COCl/sub 2/ and CO hazards. The major arc products in the 75W% C/sub 2/Cl/sub 4/ + 25W% mineral oil systems are HCl and CCl/sub 4/, and HCl would present the principal arc failure hazard. The minor products include COCl/sub 2/ and H/sub 2/, and COCl/sub 2/ would present a low probability of toxicity hazard. The levels of H/sub 2/ were well below the explosive limits of H/sub 2/ and air. It was concluded that failure arc products from these C/sub 2/Cl/sub 4/ fluid based transformers should not be hazardous in most instances of failure, and that simple precautions would be sufficient to assure safe access and handling. 6 figs., 11 tabs.

Research Organization:
Springborn Labs., Inc., Enfield, CT (USA); Westinghouse Research and Development Center, Pittsburgh, PA (USA)
OSTI ID:
6104397
Report Number(s):
EPRI-EL-4497; ON: TI86920211
Country of Publication:
United States
Language:
English