A transformer including a primary circuit with a primary inductor, a first secondary circuit with a first secondary inductor that is galvanically isolated from the primary inductor and coupled to the primary inductor, a second secondary circuit with a second secondary inductor that is galvanically isolated from the primary inductor and coupled to the primary inductor. The second secondary inductor is implemented redundantly with respect to the first secondary inductor, in particular such that the first secondary inductor encloses the second or the second encloses the first. The first and second secondary inductors are connected to one, or each to one, DC voltage source as well as each to a test circuit with a tapping point for tapping off a test voltage.

A transformer including a primary circuit with a primary inductor, a first secondary circuit with a first secondary inductor that is galvanically isolated from the primary inductor and coupled to the primary inductor, a second secondary circuit with a second secondary inductor that is galvanically isolated from the primary inductor and coupled to the primary inductor. The second secondary inductor is implemented redundantly with respect to the first secondary inductor, in particular such that the first secondary inductor encloses the second or the second encloses the first. The first and second secondary inductors are connected to one, or each to one, DC voltage source as well as each to a test circuit with a tapping point for tapping off a test voltage.

First and second coils are disposed coaxially with a gap provided therebetween and are configured to mutually cancel out magnetic fields provided thereby. A receptacle portion that defines a space traversing at least a portion of a magnetic flux produced by the coils is provided, and a magnetic powder is contained in the receptacle portion so as to occupy a portion of the space. The magnetic powder moves within the space, and this movement produces a change in the magnetic flux. This change in the magnetic flux appears in the form of a change in the inductance value.

First and second coils are disposed coaxially with a gap provided therebetween and are configured to mutually cancel out magnetic fields provided thereby. A receptacle portion that defines a space traversing at least a portion of a magnetic flux produced by the coils is provided, and a magnetic powder is contained in the receptacle portion so as to occupy a portion of the space. The magnetic powder moves within the space, and this movement produces a change in the magnetic flux. This change in the magnetic flux appears in the form of a change in the inductance value.

Apparatus and associated methods relate to a linear variable differential transformer (LVDT) probe. The LVDT probe includes a plunger rod and a metal sheet formed into a cylinder with a C-shaped cross-section, the metal sheet configured to couple to the plunger rod. In an illustrative example, the coupling may be an interference fit aided by spring retention forces of the metal sheet. The metal sheet may be stamped, formed and applied to the plunger rod without annealing. In another example, the C-shaped metal sheet may be welded to the plunger rod at a distal and/or proximal end. The ratio of relative electromagnetic permeability of the metal sheet to the plunger rod may be greater than 10.

Apparatus and associated methods relate to a linear variable differential transformer (LVDT) probe. The LVDT probe includes a plunger rod and a metal sheet formed into a cylinder with a C-shaped cross-section, the metal sheet configured to couple to the plunger rod. In an illustrative example, the coupling may be an interference fit aided by spring retention forces of the metal sheet. The metal sheet may be stamped, formed and applied to the plunger rod without annealing. In another example, the C-shaped metal sheet may be welded to the plunger rod at a distal and/or proximal end. The ratio of relative electromagnetic permeability of the metal sheet to the plunger rod may be greater than 10.

A linear variable differential transducer (LVDT) includes a primary coil, a first secondary coil, and a second secondary coil. Each of the first and second secondary coils comprises a wound portion that is wound around a longitudinal axis of the LVDT, and first and second non-wound portions at either end of the wound portion. The wound portion meets the first and second non-wound portions at locations that are separated from each other in a direction along the longitudinal axis.

A linear variable differential transducer (LVDT) includes a primary coil, a first secondary coil, and a second secondary coil. Each of the first and second secondary coils comprises a wound portion that is wound around a longitudinal axis of the LVDT, and first and second non-wound portions at either end of the wound portion. The wound portion meets the first and second non-wound portions at locations that are separated from each other in a direction along the longitudinal axis.

An electromagnetic device is disclosed, the electromagnetic device comprising a core support having an exterior surface comprising at least one radial protrusion, a tubular magnetic core positioned around a portion of the length of the core support, the tubular magnetic core having an interior surface, at least one indent located in the interior surface of the tubular magnetic core, wherein the at least one protrusion is located within the at least one indent to prevent relative longitudinal movement between the core support and tubular magnetic core, and a primary coil and at least one secondary coil, each coil positioned around a portion of a length of the tubular magnetic core.

An electromagnetic device is disclosed, the electromagnetic device comprising a core support having an exterior surface comprising at least one radial protrusion, a tubular magnetic core positioned around a portion of the length of the core support, the tubular magnetic core having an interior surface, at least one indent located in the interior surface of the tubular magnetic core, wherein the at least one protrusion is located within the at least one indent to prevent relative longitudinal movement between the core support and tubular magnetic core, and a primary coil and at least one secondary coil, each coil positioned around a portion of a length of the tubular magnetic core.