Current sensor for medical devices including connector cables

• Main Authors: RICHARD K THOMPSON, ERNESTO G SEVILLA
• Format: Patent
• Language: English
• Published: 18.12.1996
• Edition: 6
• Subjects: DIAGNOSIS; HUMAN NECESSITIES; HYGIENE; IDENTIFICATION; MEASURING; MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES; MEDICAL OR VETERINARY SCIENCE; PHYSICS; SURGERY; TESTING

A current sensing device enables sensing the current being delivered from a source to a load at a medical implement connected to the distal end of a primary conductor connected between the source and the load in situations wherein distributed capacitance between the primary conductor and a return path to the source prevents a measurement of current at the source end of the primary conductor from being an accurate measurement of the delivered current. The current sensing device comprises a reference conductor which is located beside and twisted together with the primary conductor along the length thereof but which terminates short of, and is not connected to, the medical implement load, and a subtractor for subtracting the current flowing through the reference conductor from the total load current flowing to the medical implement so as to offset the effect of the distributed capacitance and to thereby produce a current measurement corresponding to the delivered current. The subtractor can comprise a current transformer through which the conductors extend in opposing relation. An integrity detector monitors whether the reference conductor is intact.