Back to results
US 6,825,650 B1Granted
Current measuring probe and electrical energy meter for use therewith
AssigneeSuparules Limited
InventorsMichael McCormack, Thomas Sorensen
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeSuparules Limited
InventorsMichael McCormack, Thomas Sorensen
Estimating the term…
An electrical energy meter comprises an electrically insulating housing (10) for securing relative to least two mains cables (22,24) each having a conductive core surrounded by a sheath of insulating material. The housing includes respective electrical contacts for piercing the insulating sheath of each cable, a current probe for measuring current flowing in at least one of the cables, and circuit means for calculating and displaying electrical energy as a function of the voltage across the contacts and the output of the current probe. An improved current probe is employed comprising a series of Rogowski coils equally spaced around the circumference of a circle, with the gap between two adjacent coils permitting the current-carrying conductor to be introduced into the loop. An alternative current probe employs two such concentric loops of coils, enabling compensation for the effects of external current source pickup.
A current probe for measuring current in a conductor, comprising a plurality of relatively fixed coils which define, and are substantially equally spaced apart along, a notional closed path surrounding the conductor, the coils being connected in series in such manner that an unobstructed gap is left between one pair of adjacent coils to enable the conductor to be introduced inside the closed path, wherein said coils are arranged in two concentric loops of coils, each loop being connected in series, and each loop having a gap between two of the coils in the loop, said gaps enabling introduction of the conductor into the interior of the concentric loops.
An electrical energy meter comprising an electrically insulating housing for securing relative to at least two mains cables each having a conductive core surrounded by a sheath of insulating material, the housing including respective electrical contact means for piercing the insulating sheath of each cable to make contact with the core, sensing means for providing an output corresponding to the current flowing in at least one of the cables, and circuit means for calculating and displaying electrical energy as a function of the voltage across the contact means and the output of the sensing means, said sensing means comprising a plurality of relatively fixed coils which define, and are substantially equally spaced apart along, a notional closed path surrounding the said at least one mains cable, the coils being connected in series in such manner that an unobstructed gap is left between one pair of adjacent coils to enable the said at least one mains cable to be introduced inside the closed path.
Dependencies are inferred from the claim text.