Ralston DCAP-PV hand pump

Calibrating pressure transmitters in the field requires a hand pump that can generate pressure and vacuum easily and then control pressure to precise test points. In the case of differential pressure transmitters, the user must calibrate both the high and low side of the DP cell. This means the fine adjust control must be precise at 12 kPa as well as 3.5 MPa.

The DCAP-PV hand pump allows the user to control pressure or vacuum easily and move through their tests without worrying about leaks when calibrating gauges. The Ralston Quick-test system of hoses and connectors lets the user connect without thread tape to each adapter and in many cases also to the device being calibrated without a wrench.

The fine adjust piston on the DCAP-PV also lets the user open or close a pressure switch easily. Actuating a pressure switch multiple times to ensure it is working correctly can be achieved easily.

The pump works well for calibrating flow computers, which require precise control of pressure to each side of the differential pressure cell. The pump and hose need to have a low volume so that the user is not spending a lot of time compressing air just to fill a hose. The connections on most flow computers can be accessed with Ralston Quick Connect adapters without thread sealant. If some test points are below ambient pressure, the pump can be used to pull a vacuum.