Using a proven float and tape level measurement technique, these instruments have been the main stay of the petroleum automatic tank gauging market for over 75 years.

Changes in the liquid level inside the tank raise or lower a large stainless steel float. The float is attached to a powerful negator spring via a perforated tape. The negator spring provides constant tension, which balances the float on the liquid level. The perforated tape engages pins on a sprocket wheel that, in turn, drives the counter assembly.

When a gauge board is used to display level in a float & tape system, the negator spring is replaced by a counter weight system. The liquid level in feet and inches, or meters and decimeters is displayed on the gauge counter or indicated on a gauge board.This simple design and operation allows the gauge to perform with negligible maintenance throughout its working life.