Proportional exhaust sampler system and control means.

摘要

A testing apparatus for measuring the particulate and/or gaseous content of an exhaust source for use in evaluating the exhaust emissions of internal combustion engine provides both fixed flow and proportional flow control of the diluted particulate containing sample. The sample is diluted with carefully metered, clean dry air by means of one or more hybrid electrical-fluid control circuits for remarkably improved response time and accuracy.