A device for a current limiter, the device comprising: at least one coil assembly adapted to carry a current, the coil assembly comprising: a first coil, comprising a first superconducting element, adapted to carry a first portion of said current; a second coil, comprising a second superconducting element, adapted to carry a second portion of said current; and cooling means for cooling the first and second superconducting element below their critical temperatures, wherein said first and second coil (14, 16) are arranged such that, when said first and second superconducting element are each in a superconducting state and said coil assembly carries said current, a magnetic field generated by said first portion of said current in said first coil is substantially cancelled by a magnetic field generated by said second portion of said current in said second coil; wherein said device is adapted such that, in use, when said first and second coil (14, 16) are thermally coupled to said cooling means, said first and second superconducting element are maintained at different temperatures so that the first superconducting element has a lower critical current than the second superconducting element for undergoing a transition from a superconducting state to a normally conducting state, characterized in that said coil assembly further comprises a former for supporting said first and second coil (14, 16), said former being adapted to thermally couple said first and second coil to said cooling means. at least one coil assembly adapted to carry a current, the coil assembly comprising: a first coil, comprising a first superconducting element, adapted to carry a first portion of said current; a second coil, comprising a second superconducting element, adapted to carry a second portion of said current; and cooling means for cooling the first and second superconducting element below their critical temperatures, a first coil, comprising a first superconducting element, adapted to carry a first portion of said current; a second coil, comprising a second superconducting element, adapted to carry a second portion of said current; and cooling means for cooling the first and second superconducting element below their critical temperatures, wherein said first and second coil (14, 16) are arranged such that, when said first and second superconducting element are each in a superconducting state and said coil assembly carries said current, a magnetic field generated by said first portion of said current in said first coil is substantially cancelled by a magnetic field generated by said second portion of said current in said second coil; wherein said device is adapted such that, in use, when said first and second coil (14, 16) are thermally coupled to said cooling means, said first and second superconducting element are maintained at different temperatures so that the first superconducting element has a lower critical current than the second superconducting element for undergoing a transition from a superconducting state to a normally conducting state, characterized in that said coil assembly further comprises a former for supporting said first and second coil (14, 16), said former being adapted to thermally couple said first and second coil to said cooling means.