Patent ID: 11879326
Assignee: HALLIBURTON ENERGY SERVICES, INC.
Field: Measurement (Instruments)
Classification: CPC E  G | IPC E  G

Claim 7:
8. A method comprising:
deploying one or more magnetically permeable objects into a tubular, wherein the tubular is disposed in a wellbore;
counting the one or more magnetically permeable objects that pass a sensor to produce a defined count, the sensor comprising:
a first permanent magnet,
a second permanent magnet, and
a magnetic field sensor disposed between opposing poles of the first permanent magnet and the second permanent magnet, wherein the first permanent magnet and the second permanent magnet each produce a magnetic field;

measuring, via the magnetic field sensor, one or more changes in the magnetic field of at least one of the permanent magnets as one or more magnetically permeable objects passes by the magnetic field sensor;
generating, via the magnetic field sensor, a voltage output based on the one or more changes, the voltage output including a positive voltage peak and a negative voltage peak;
determining a direction of the one or more magnetically permeable objects that pass the sensor based a sequence of the positive voltage peak and the negative voltage peak;
updating the defined count based on the direction of the one or more magnetically permeable objects, wherein the defined count will be increased with a first sequence of the positive voltage peak and the negative voltage peak, and wherein the defined count will remain unchanged or decremented with a second sequence of the positive voltage peak and the negative voltage peak; and
electrically triggering a downhole device based on the updated defined count.