A medical connector comprising: a fluid inlet port for removable engagement with a connection port of a fluid injector system having a housing, said connection port being formed on a multi-use disposable set (MUDS) that is removably connected to the fluid injector system to establish a fluid connection therewith, whereas the connection port is recessed within an opening formed on the housing; a waste outlet port configured for removable engagement with a waste inlet port of a fluid injector system to establish a fluid connection therewith; a patient fluid line connected, at a first end, to the fluid inlet port and removably connected, at a second end, by a patient fluid line connector to the waste outlet port, thereby establishing a fluid connection between the fluid inlet port and the waste outlet port, wherein fluid flow through the patient fluid line is unidirectional from the first end to the second end, wherein the medical connector further comprises a locking mechanism for removably securing the medical connector to the MUDS, wherein the locking mechanism comprises a flexible tab that is deflectable between an engaged position with a receiving slot on the MUDS and a disengaged position by deflecting at least a portion of the flexible tab; and at least one sensor element comprising a sensing fin on the flexible tab having one or more reflective surfaces that reflect visible or infrared light to be detected by at least one sensor seated and secured within a respective mount formed on the housing 102 of the fluid injector system for detecting a presence or absence of the sensing fin, wherein detection of the presence of the at least one sensor element by the at least one sensor indicates that the medical connector has been inserted or installed in the connection port; and wherein the patient fluid line and patient fluid line connector are configured for being disconnected from the waste outlet port for delivering fluid from the fluid inlet port to a catheter, vascular access device, needle, or additional fluid path, while the waste outlet port remains engaged with the waste inlet port of the fluid injector system. a fluid inlet port for removable engagement with a connection port of a fluid injector system having a housing, said connection port being formed on a multi-use disposable set (MUDS) that is removably connected to the fluid injector system to establish a fluid connection therewith, whereas the connection port is recessed within an opening formed on the housing; a waste outlet port configured for removable engagement with a waste inlet port of a fluid injector system to establish a fluid connection therewith; a patient fluid line connected, at a first end, to the fluid inlet port and removably connected, at a second end, by a patient fluid line connector to the waste outlet port, thereby establishing a fluid connection between the fluid inlet port and the waste outlet port, wherein fluid flow through the patient fluid line is unidirectional from the first end to the second end, wherein the medical connector further comprises a locking mechanism for removably securing the medical connector to the MUDS, wherein the locking mechanism comprises a flexible tab that is deflectable between an engaged position with a receiving slot on the MUDS and a disengaged position by deflecting at least a portion of the flexible tab; and at least one sensor element comprising a sensing fin on the flexible tab having one or more reflective surfaces that reflect visible or infrared light to be detected by at least one sensor seated and secured within a respective mount formed on the housing 102 of the fluid injector system for detecting a presence or absence of the sensing fin, wherein detection of the presence of the at least one sensor element by the at least one sensor indicates that the medical connector has been inserted or installed in the connection port; and wherein the patient fluid line and patient fluid line connector are configured for being disconnected from the waste outlet port for delivering fluid from the fluid inlet port to a catheter, vascular access device, needle, or additional fluid path, while the waste outlet port remains engaged with the waste inlet port of the fluid injector system.