Electrical heating element and method of measuring a filling level
AssigneeAreva GmbH
InventorsSacha Kaercher, Wolfgang Vogt, Stefan Pfleger, Wilfried Harfst
Life of this patent
Estimating the term…
Abstract
A pencil-shaped electrical heating element, in particular for application in a device for measuring filling level in a liquid container, in particular in a reactor chamber of a nuclear plant, contains an electrically-conducting sleeve and at least one electric line embedded therein which is in conducting contact with the sleeve. The electrical line has at least two line sections with differing electrical properties and/or thermal conductivities.
Claims8
An apparatus for measuring a filling level in a liquid container, the apparatus comprising:
- a number of thermocouples;
- a heating element having an electric line, said electric line having at least one first line portion forming a cold zone and a second line portion forming a heating zone, with said second line portion having a considerably higher resistivity than said first line portion, and with a temperature dependence of resistivity in said first line portion being considerably greater than in said second line portion;
- means for measuring a total resistance of said electric line;
- and
- means for determining a temperature in a surrounding area of said first line portion on a basis of a measured total resistance of said electric line.
A method for operating an apparatus for measuring a filling level in a liquid container, the apparatus having a number of thermocouples and a heating element with an electric line, the electric line having at least one first line portion forming a cold zone and a second line portion forming a heating zone, with the second line portion having a considerably higher resistivity than the first line portion, and with a temperature dependence of a resistivity in the first line portion being considerably greater than in the second line portion, which comprises the steps of:
- measuring a total resistance of the electric line;
- and
- ascertaining a temperature in a surrounding area of the first line portion on a basis of a measurement value of the total resistance of the electric line.
Dependencies are inferred from the claim text.