Abstract: A rotor assembly for a peristaltic pump is provided. Each of a first pair of roller assemblies includes a first roller portion having a first diameter and a second roller portion having a second diameter. The first diameter is larger than the second diameter. Each of a second pair of roller assemblies includes a first roller portion having a first diameter and a second roller portion having a second diameter. The first diameter is smaller than the second diameter. The first and second pairs of roller assemblies are positionable around a circumference of a hub such that the first roller portion of the first pair of roller assemblies is aligned with the first roller portion of the second pair of roller assemblies and the second roller portion of the first pair of roller assemblies is aligned with the second roller portion of the second pair of roller assemblies.

Abstract: A pump can include a pump head, a body housing, a motor disposed within the body housing, and a motor shaft extending from the motor. The pump head can include a sensor, at least a first interface portion, and at least a first elongate conductor electrically connecting the sensor to the at least a first interface portion. The body housing can include at least a second interface portion and at least a second elongate conductor electrically connecting the at least a second interface portion to pump electronics. The sensor can be configured to sense when the at least a first interface portion does not contact the at least a second interface portion. When the at least a first interface portion does not contact the at least a second interface portion and the pump head is removed from the body housing, the pump head can be pivotable relative the motor shaft such that an orientation of the pump head can be changed with respect to the body housing.