Harvard Apparatus’sPHD OEM pumping module is designed for high pressure, accurate, andprecise dispensing of fluid to a process or instrumentation. With the “Program” and “Auto Fill” buttons, the pump can be programed with a sequence of pumping steps. Users can start orstop the pump, change the pumping direction, change the flowrate, pumpa precise volume and stop, pause the pump, and ramp up or ramp downthe flowrate.The Auto Fill keyis useful when the user would like to deliver a large volume of fluid.The user sets a target volume and then programs the refill volume forthe syringe. The pump will automatically refill the syringe as manytimes as required to reach the target volume. Then the pump willautomatically stop. This process does require the use of a valve. On the back side of the pump are two RS232 ports. One is for input froma computer, and the second is for output when daisy chaining more thanone pump together. The I/O port is a nine-pin D sub connector and is used for TTL control. Also on the back isthe universal power entry module, which encompasses the ON/OFF switch,fuse, and universal power supply. This power supply will accept powerinput from 110 to 240 VAC, 50/60 Hz. The mechanical stop collars causethe pump to stop automatically to protecting syringes.