REMOTE SAMPLING BYPASS FOR A GAS ANALYSER

摘要

Described herein is a gas detection system (5) including a housing (10) having an inlet (20) in fluid communication with an atmosphere; an analyzer (25) within the housing (20) and configured to detect and measure a gas species in the atmosphere using a gas sensor (37); and a pneumatic system (60) contained within the housing (10) and in fluid communication with the inlet (20) to draw an air sample from the atmosphere. The pneumatic system (60) includes a pump (15); a low flow branch (65) in fluid communication with the pump (15) and having an airflow sensor (90) and a first orifice (85); and a high flow branch (70) in fluid communication with the pump (15) and having a second orifice (95). Such a system is particularly suitable for remote sampling because it prevents the high flow needed for remote sampling to be directed towards the gas sensor withstanding only low flow. Related apparatus, systems, methods and/or articles are described.

主权项

1. A gas detection system comprising:
a housing having an inlet in fluid communication with an atmosphere; an analyzer within the housing and configured to detect and measure a gas species in the atmosphere using a gas sensor; and a pneumatic system contained within the housing and in fluid communication with the inlet to draw an air sample from the atmosphere, the pneumatic system comprising:
a pump;a low flow branch in fluid communication with the pump and having an airflow sensor; anda high flow branch in fluid communication with the pump and having a second orifice. wherein:
the air sample is divided into a first portion that flows through the low flow branch and a second portion that flows through the high flow branch, andair flow through the pneumatic system is controlled by the low flow branch such that a flow rate in the high flow branch of the pneumatic system is a function of the flow rate created by the low flow branch.