A connector interface system includes a cap to connect to a reservoir to form a reservoir/cap unit for installation into an infusion pump device. The cap has at least one receptacle for receiving one or more detectable features comprising at least one disc-shaped member, for detection by at least one sensor element on the infusion pump device when the reservoir of the reservoir/cap unit is received in a reservoir receptacle of the infusion pump device. The at least one detectable feature has at least one detectable parameter that is associated with one or more characteristics of the cap, the reservoir, the infusion pump device, a cannula associated with the cap or a tubing connected between the cap and the cannula.