Mettler Toledo GPro 500 TDL in-situ oxygen sensor

Mettler Toledo’s GPro 500 TDL sensor is claimed to offer exceptional measuring performance and easy installation, and to require little or no maintenance. Being a tunable diode laser (TDL) gas analyser, no sample extraction or conditioning is necessary, it exhibits low drift, and it is immune to interference from moisture, dust or background gases.

Other TDL gas solutions are of a cross-stack design, meaning that the receiver must be positioned directly opposite the laser source. This causes installation difficulties and requires regular, troublesome realignment. The GPro 500 incorporates a probe that reflects the laser beam back to the receiver in the sensor head, therefore alignment is never required. And because the laser beam travels twice through the gas stream, the optical path length is doubled, resulting in more accurate O₂ measurement.

The company’s intelligent sensor management (ISM) technology adds to the features of the sensor by incorporating predictive diagnostics that continually assess the optical path quality and indicate when cleaning is required, before measurements are affected. Other than yearly verification and occasional cleaning of the optics, no other maintenance is required.