Circuit for transmitting a measurement current from an intrinsically safe sensor to a non-intrinsically safe area
CA 2209208 C · Owner: Endress + Hauser Wetzer Gmbh + Co. Kg · Inventors: Ahr, Robert
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This circuit arrangement comprises a transformer (2) for transmitting a measurement current (I) which is output by, a sensor arrangement (1) at a measurement location situated in an intrinsically safe area (10), to a non-intrinsically safe area (20), in which a current measuring resistor (5) is situated. A DC converter (3) serves for the power supply of the sensor arrangement. A transformer (2) belongs to the DC converter (3), has a primary winding which faces the, non-intrinsically safe area two identical partial windings, (21, 22) connected in series in the same sense and a, single secondary winding (23), which faces the intrinsically safe area. A first end of the current measuring …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed June 26, 1997 and granted September 12, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 26, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 26, 2019.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.