High voltage non-track material HVTM

12 months natural weathering Swindon, England. Non tracking - no change from original 

2000 hours WeatherOmeter conditions Non tracking - less erosion than control 

Relative humidity Xenon arc on 50 - 2% Xenon arc off 98 - 2% Black panel temperature Xenon arc on 50 - 2 C Xenon arc off 25 - 2 C Contaminant concentration Ozone 20 pphm Sulphur 20 pphm dioxide As surface wetted more readily resulting in scintillations over larger areas, erosion effect non concentrated in one spot of surface as is usual. 

Thermal ageing 500hrs 125 C 125hrs 150 C Non tracking - no significant change from original 

Natural aging of Thermofit HV under mechanical and electrical stress 

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