Title :
Dynamic relaxation time measuring system for powders and liquids
Author_Institution :
Appl. Electrostatic Res. Centre, Western Ontario Univ., Ont., Canada
Abstract :
With the increasing industrial use of electrostatic systems to coat surfaces, the relaxation time constants of the powder which is being applied electrostatically is a key intrinsic property of the coating material. The measuring system described involves: a powder compacting unit with a vibrator, a high-voltage power supply for corona charging, and an electric flux-decay-versus-time monitoring electrometer. The system allows evaluation of a realistic relaxation time constant, particularly for packed powder, from various levels of charge. To substantiate the operation of the system, tests results are presented for sugar, polyethylene, Arizona road dust as well as for a liquid dielectric transformer oil
Keywords :
charge measurement; corona; electric charge; electrostatic devices; insulating oils; powders; power supplies to apparatus; spray coating techniques; Arizona road dust; charge relaxation time; corona charging; electric flux-decay-versus-time monitoring electrometer; electrostatic systems; high-voltage power supply; liquid dielectric transformer oil; liquids; packed powder; polyethylene; powder compacting unit; powders; relaxation time measuring system; sugar; surface coating; vibrator; Coatings; Dielectric liquids; Electric variables measurement; Electricity supply industry; Electrostatic measurements; Powders; Power measurement; Surface charging; Time measurement; Vibration measurement;
Conference_Titel :
Industry Applications Society Annual Meeting, 1992., Conference Record of the 1992 IEEE
Conference_Location :
Houston, TX
Print_ISBN :
0-7803-0635-X
DOI :
10.1109/IAS.1992.244390
