Pressure controller 202

The Model 202 maintains a constant flow rate as long as the upstream (inlet) pressure is held constant during downstream pressure fluctuations from column switching, temperature programming, sequence reversal, or backflushing — even if the fluctuation is to within 10 psi of the supply pressure. A user-variable span adjustment permits it to be used for a variety of flow ranges. The span valve can adjust the flow range from a minimum flow as small as 5.0 mL/min up to a maximum flow of 1.6 L/min (N2 at 40 psi). After the span is adjusted, the control stem has a full 10 turns of resolution between zero flow and the maximum rate. When the controller is equipped with a Spectrol digital dial, settings are reproducible to better than 1%. The Model 202 comes standard with 1/8" NPT female pipe threads. Adapters to go from pipe to 1/16" OD tubing are included. Other fittings are available NOTE: With all our flow controllers, the inlet pressure must exceed the outlet pressure by 10 psi.