Siemens Sitrans SL gas analyser

Siemens Sitrans SL is a diode laser gas analyser featuring an inline reference cell filled with a non-interfering reference gas. This allows for a fast and non-contact measurement of gas concentrations in process or flue gases. The unit can be used in various industries and applications, such as process control and as combustion control for boilers and municipal waste incinerators. It is also effective for measuring minimum or maximum concentrations limits of oxygen in explosive-proof environments.

The measuring principle of the unit is based on the specific light absorption of different gas components using light from a laser diode that is sent from the transmitter through the process gas to the detector on the receiver side. As the band width of the laser light is narrow, only the gas component of interest will interact with it. Other process influences, such as dust and temperature, are easily eliminated due to the good compensation capabilities of this technique. The characteristics of the laser allow single-line spectroscopy free of interferences.

The unit consists of a cross-duct sensor pair — transmitter and receiver. The entire analytical instrument is fitted into these two enclosures, which are interconnected with one cable. Another cable is connected from the receiver providing the power and the user interface. The receiver hosts a local user interface (LUI) which is operated with an IR remote control.