Retractable current leads are available in various versions to further reduce heat load while the magnet is in persistent mode. This option is available in several current ratings. The construction of retractable versions is in two sections. The lower section (Guide Tube) is permanently mounted inside the cryostat. The upper section can be disconnected and retracted into the cryostat neck. Liquid helium consumption is significantly reduced because the thermal path to the liquid helium bath is broken. Lead retractors are available to easily retract and insert the current leads. Available in standard designs of 50,100 and 150 Amps with custom design available by request.
NOTE: Care must be exercised during manipulation of retractable current leads to assure the presence of positive pressure within the guide tube. Negative pressure conditions can allow for the introduction of ambient air to back-fill into the guide tube creating and ice blockage. This blockage may prevent the user from being able to reattach the current leads which would require the system to be warmed.