Electricity: measuring and testing – Impedance – admittance or other quantities representative of... – Lumped type parameters
Patent
1998-04-29
2000-09-05
Metjahic, Safet
Electricity: measuring and testing
Impedance, admittance or other quantities representative of...
Lumped type parameters
324673, 324674, 324694, G01R 2728, G01R 2726, G01R 2708
Patent
active
061148636
ABSTRACT:
An improved process for determining the presence of water in a material is disclosed. A set of electrodes is placed on the surface of a layer of the material being monitored, and an electric field is established therebetween. The phase angle for the electric field at a pre-selected frequency is measured, and compared with a predetermined phase angle for a dry portion of the material. A significant difference between the phase angle for the material being monitored and the predetermined phase angle is indicative of the presence of water in the material. The material being monitored may be an electrical insulating material, e.g., for conductive components in water-cooled electrical generators. Electrical generators monitored in this manner are also within the scope of this disclosure.
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Krahn John Raymond
Reed Clive William
General Electric Company
Ingraham Donald S.
Kerveros James C
Metjahic Safet
Stoner Douglas E.
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