Abstract
Consideration of the timing circuitry employed in the Sage pump model 341 A indicates that the pump's performance will be strongly affected by component tolerances, and our measurements have confirmed this impression. Thus, delivered, flow rates may deviate considerably from those indicated on the calibration chart; our instrument was about 10% slow at all settings. For many’ applications it will be necessary to carry out a full calibration procedure, which should be repeated following any repairs to the electronic circuitry. The pump also suffered from drift at certain settings because un inappropriate component had been used in the timing circuitry. These findings will also apply’ to the Sage pump models 240 A and 242 A, which employ, similar timing circuitry to the 341 A. When precautions are taken to overcome these problems, the pump's performance is satisfactory. for both clinical use and some laboratory applications.