摘要 |
A magnetic system for determining an operating position of a downhole tool. The system includes an array of magnets operable to produce a magnetic field that is operably associated with a stationary component of the downhole tool. A moveable component of the downhole tool has at least first and second positions relative to the stationary component. In the first position, the moveable component has a first degree of interference with the magnetic field. In the second position, the moveable component has a second degree of interference with the magnetic field. A magnetic field detector is operable to be run into the wellbore and moved relative to the downhole tool such that the position of the moveable component relative to the stationary component is determined by detection of a magnetic signature produced by the moveable component and the array of magnets. |