1 Polluted insulators may flashover at any time under disadvantage weather conditions.

2 AC flashover voltage, voltage gradient along the leakage distance and the valid creepage distance of polluted insulators are related to its materials and configuration.

3 The relationship of hydrophobicity and wet flashover voltage of composite insulators is also discussed in this paper.

4 Pollution flashover performance is one of the key issues of external insulation selection of transmission lines.

5 This paper summarizes the relevant research of surface flashover switch.

6 The test shows that the flashover voltage of polluted insulators regularly decreases with the increasing of the altitude.

7 The flashover voltage of iced insulators of transmission lines is affected by the electrical characteristic of ice.

8 The flashover voltage of polluted composite insulators is decreased with increase of SDD and the fog conductivity in acid fog and salt fog.

9 Overvoltage level and insulation flashover characteristics are considered in the insulation coordination part as well as safety, reliability, construction and operation cost.

10 This paper takes flashover as a transition point and concludes present international forecast methods of temperature in pre-flashover and post-flashover compartment fires.

11 But Emmons observed that at flashover, the hot smoky layer instantly drops down.

12 It is presented that the flashover voltage of parallel insulator is lower than that of single insulator,[] while the V type insulator's is almost the same as that of single one.

13 Most lighting along the railway may cause insulator flashover in catenary.

14 The accident of pollution flashover on power transmission line happened frequently, which brought hidden trouble to the safe operation of power network.

15 Because of rapid rising rate of nanosecond pulse, flashover voltage can reach a higher value after discharge channels have been built.

16 Reflux of electron of high voltage vacuum diode is one of the main factors to cause the dielectric surface flashover.

17 So there is important implication value and academic value to systemic investigation of the effect of the existence of air gap to the flashover voltage along the ice-covered insulators.

18 Insulator should withstand power frequency voltage, switchingvoltage and lightning impulse voltage, shouldn't flashover under pollution.

19 Composite insulator has been widely used in high-voltage electric power transmission system because of its advantages in light weight, anti-pollution flashover and less routine maintenance.

20 The discharge at the top of icicle is one of the main factors influencing flashover voltage when the air gap amid the sheds of ice-covered insulators is not bridged.

21 The ignition of both deal and fir blocks were tested a bench scale flashover test apparatus.

22 Experimental results shows that the polarity of surface charges a great influence on impulse flashover voltages.

23 At the helicopter during the aerial survey, according to the action line protection, the use of helicopters can be inspected Detected lightning flashover point of failure.

24 For various assembled forms, the effects of the air pressure on the flashover voltage of the horizontal string are most obvious.

25 The icing disasters of transmission line such as line trip, break line, pole collapse, insulator flashover and communication interruption have resulted in huge economic lose of nation.

26 Transmission line regelation may cause conductor galloping, pole leaning or collapse, conductor breaking or insulator flashover etc.

27 Ice coating on overhead contact line not only will influence contact line's sag and pole capability, but will influence the flashover voltage of insulator.

28 Separating the water curtain of the melting ice water is the measure and method of raising ice insulator flashover voltage.

29 All results will improve the understanding on discharge atmospheric icing and prevent the further flashover occurrence.

30 With the development of national economy, promotion of power capacity and transmission voltage level, insulator flashover takes place frequently, which causes enormous economic losses.

31 First, based on a pollution flashover probability model for insulators under certain operation voltage and conditional probability, the fault probability of transmission lines was obtained.

32 The dissipating current and current suppressionafter flashover of semiconductor lightning eliminator are discussed in this paper.

33 The results indicate that flashover in building fires is a phenomenon of swallowtail catastrophe.

34 The correction method of switching impulse flashover voltage under high altitude was discussed and the altitude correction coefficient was given.

35 The room temperature vulcanizing(RTV) silicone rubber coating on the surface of insulator may increase the flashover voltage of contaminated insulator.

36 In comparison with simulation tests, the mechanism of guano - caused flashover is basically clarified.

37 For the insulator investigated the 50 % flashover voltage is reduced by 23.4 %.

38 The current and voltage response of surge discharge circuit to impulse flashover voltage test system is analyzed.

39 Silicone material has been widely used in power system to prevent pollution flashover of outdoor insulation.

40 The ice flashover accident of transmission line insulator is harmful for transmission line safe operation.

41 The room temperature vulcanized (RTV) silicone rubber coating on the surface of insulator can incrcase the flashover voltage of insulators due to the migration of hydrophobicity of RTV coating.

42 Although the AC flashover performance of a polluted insulator has been studied well, there is few study on the valid coefficient of creepage distance of different types of insulators.

43 This paper expounds the mechanism of insulators contamination flashover and the principle of leakage current monitor.

44 By physical observation , flashover in building fires is a suggestive of a catastrophe process.

45 The insulation characteristic of insulator in vacuum is researched in the process of the high voltage breakdown along the insulator surface in vacuum, which is called vacuum surface flashover.

46 Icing weight and icing water conductivity are the two independent parameters which affect on the lowest AC flashover voltage of icing composite insulators.

47 The partial discharge and surface charge on organic glass are easier been observed than those on polyethylene, and the organic glass insulator flashover voltage is lower.

48 The critical flashover current reduces with the decrease of air pressure.

49 The effect of charges remaining on a dielectric plate upon the 50% impulse surface flashover voltage U_(50) in the non-uniform field(rod-plane gap)is investigated.

50 Before flashover occurs, a person in a burning room may crawl to safety along the floor.

51 The scheme that the auxiliary contact of the switch is taken as the auxiliary criterion composed of the flashover protection is not correct.

52 It was proved that this device can predict the occurrence of flashover successfully.

53 This is helpful for increasing the resistance to surface flashover and the high-voltage breakdown strength of solid insulators in high-vacuum.

54 To intensify basic external insulation level of power system-fundamental way for prevention of large-scale pollution flashover.

55 This method a simple understanding of the radiation processes in compartment fires such flashover.

56 Salt-water fog also cause an increase of impulse flashover voltage but a slight decrease of AC flashover voltage.

57 The basic measure to protect from large area pollutant flashover is to increase overall external insulation level for transmission and substation equipment.