SKC Limited Pocket Pump MTX - Manual (Page 19)

www.skcltd.com 210-PMTXM Issue F Page 17
Operating the Pocket Pump in Constant Flow Mode
When the flow rate has been satisfactorily calibrated press the button to return to
RUN mode. The pump will now maintain the calibrated flow rate to within ±5%.
The pump run-time data is recorded during the flow rate setting and calibration
operations. Before starting a sample run reset the run-time data.
3) Multiple Tube Sampling in Constant Flow Mode Using a Constant Pressure Controller
An alternative method to Constant Pressure mode for multiple tube sampling is to use a Constant Pressure
Controller (CPC - SKC Part No. 224-26CPC-10). The CPC is a device that generates a constant back pressure
of 10 inches of water at the outlet of the connected multiple tube holder.
Ensure that the pump is set to Constant Flow mode and set the pump flow rate to a level higher than the
combined flow rates through the tubes. The pump flow rate does not need to be accurately calibrated.
Connect the CPC between the pump air inlet port and the multiple tube holder. The short length of tubing
supplied with the CPC is connected to the pump and the multiple tube holder is connected to the side of the
CPC marked “TO SAMPLE”.
The flow rate through the individual tubes can then be calibrated using the needle valves built into the multiple
tube holder.