The subject matter of this specification can be embodied in, among other things, an identification system includes a first component having a first resistor and a second resistor, a second component having a sensor configured to sense a voltage difference between a first bus and a second bus and a selector signal output port configured to provide a first selector signal and a second selector signal, and a third component having a switching network configured to electrically connect the second bus to the first bus across one or both of the first resistor and the second resistor in response to the first selector signal, and electrically connect the second bus to the first bus across a different one of the first resistor or the second resistor in response to the second selector signal.

The subject matter of this specification can be embodied in, among other things, an identification system includes a first component having a first resistor and a second resistor, a second component having a sensor configured to sense a voltage difference between a first bus and a second bus and a selector signal output port configured to provide a first selector signal and a second selector signal, and a third component having a switching network configured to electrically connect the second bus to the first bus across one or both of the first resistor and the second resistor in response to the first selector signal, and electrically connect the second bus to the first bus across a different one of the first resistor or the second resistor in response to the second selector signal.

The subject matter of this specification can be embodied in, among other things, an identification system includes a first component having a first resistor and a second resistor, a second component having a sensor configured to sense a voltage difference between a first bus and a second bus and a selector signal output port configured to provide a first selector signal and a second selector signal, and a third component having a switching network configured to electrically connect the second bus to the first bus across one or both of the first resistor and the second resistor in response to the first selector signal, and electrically connect the second bus to the first bus across a different one of the first resistor or the second resistor in response to the second selector signal.

An apparatus for making an electrical connection between a superconducting component disposed in a cryogenic chamber and an electrical device disposed outside the cryogenic chamber is described. The apparatus includes a coil comprising a plurality of helical loops and disposed in the cryogenic chamber; and an actuator configured to compress and expand the coil between a first state and a second state. In the first state, the coil has a first electrical resistance and a first thermal conductance and in the second state the coil has a second electrical resistance and a second thermal conductance.

An apparatus for making an electrical connection between a superconducting component disposed in a cryogenic chamber and an electrical device disposed outside the cryogenic chamber is described. The apparatus includes a coil comprising a plurality of helical loops and disposed in the cryogenic chamber; and an actuator configured to compress and expand the coil between a first state and a second state. In the first state, the coil has a first electrical resistance and a first thermal conductance and in the second state the coil has a second electrical resistance and a second thermal conductance.