An apparatus includes a housing having a support surface to support a cartridge, a socket attached to the housing, and an actuator associated with the socket. The socket surface includes one or more socket positioning members, a plurality of electrical contacts and a plurality of magnets. The socket is configured to move relative to the support surface of the housing, with the one or more socket positioning members located in a fixed relation to the plurality of electrical contacts so that when the socket is spaced proximate to the support surface of the housing, the one or more socket positioning members engage with the one or more cartridge positioning members to align the plurality of electrical contacts of the socket with the plurality of electrical contact pads of the cartridge. The actuator is configured to align each magnet with a respective fluid conduit of the processing device.