When an Online Analyser or CEM system is required to measure multiple sample streams or when zero and span gases need to be diverted to a probe for validation purposes, a stream switching device is needed to control the flows.

PSA have developed the PSA 10.535 single channel system supported by the S665S200 range which are compatible with all the online analysers and can be configured to handle any usual numbers of sample streams with the ability of handling different configurations.


The units consist of a Mass Flow controller plus a number of 3-way Teflon Switching valves. A sample pump is incorporated into the unit. The stream selector can be configured for positive or negative flow applications.

The PSA 10.536 Mercury Vapour Generator can also be connected to the system to provide zero and span gases and divert these to the desired location for calibration of bias testing.

The valves are controlled via a TTL cable which connects with the PSA 10.525 Sir Galahad module.

The Mass Flow Controller is controlled though the MODBUS Protocol and connects to the PSA Online Software.

The software controls the flow of sample over the Sir Galahad and uses the Mass Flow Controller to measure the volume of sample collected.

The PSA 10.535 is a single channel unit only. The S665S200 is available in a number of valve configurations and with pumps of different voltages.

Typical two channel system


The S665S200 systems are designed so that the waste outlet of the valve can be capped in order to conserve sample or for increased safety when potentially explosive samples are handled.  

To discuss your particular requirements and for more detailed information on any of the above products please complete the Information Request Form.