Electrical liq. level indication and recording - using immersion tube with pump keeping tube clear during measurement sampling and storage

摘要

The arrangement eliminates the effects on the display, monitoring and/or recording of the measured fill value of penetration of the liq. into the immersion tube during, and immediately after, the container is filled. When an increase in level is detected the display and monitor device triggers a 'level increase' signal. An air pump connected to the immersion tube is switched on by this signal directly or via a delay for a defined adjustable period. The pumping period is chosen to be long enough to ensure that the tube is free of liq. during the periodically repeated measurement parameter sampling and storage time.