The role of spacer surface conditions in the scatter of charge accumulations in SF/sub 6/

A cylindrical epoxy spacer with different surface roughnesses was stressed under +150 kV in SF/sub 6/. It is found that artificial roughness has no significant influence on the charge accumulation. Influences come from the variation in the surface conditions of the spacer by roughening it artificially. An additional test also shows that the micro structure at the spacer surface is more responsible for the large scatter of charge accumulation than that at the electrodes.<>