Testing examples Power-frequency voltage flashover on a 35 kV disconnector. A lightning impulse flashover to the ground. Visible corona measurements on a 400 kV disconnector. A disconnector dielectric testing. A lightning impulse testing of a special tension polymeric insulator set. The wet power-frequency testing of a porcelain post insulator. A 400 kV transformer bushing testing. A partial discharge measurements test setup. An close look up on a powerfrequency flashover. A surge gap under the current impulse testing. Porcelain post insulator during wet power-frequency voltage test. Synchronous generator. Tensile machine. Thermal-mechanic chamber. The electric knight. Double tension composite insulator string during radio interference voltage test. „V“ porcelain insulator string during dry lightning impulse voltage test. Tracking and erosion test – wheel test Composite post insulator during thermal-mechanical pre-stressing. High voltage laboratory in Prague. Transformer bushing - cantilever test Transformer bushing - Temperature Rise Test Internal pressure test of hollow core insulators - test chamber for leakage gas detection On-line monitoring of gas leakage Oil-oil bushing - dielectric type testing using an insulating cylinder Oil-oil bushing - temperature rise testing Double „V" jumper insulator set