A medical fluid delivery system includes a dialysis instrument; a disposable pumping cassette operable with a pumping actuator of the dialysis instrument, the disposable cassette including or connected fluidly to a plurality of first connectors; a plurality of second connectors configured to interface with the first connectors, each second connector associated with a radio frequency (“RFID”) tag; and electronics configured to read the RFID tags via a plurality of antennae and to identify that each of the second connectors is positioned properly with respect to a proper one of the first connectors.