Macro Sensors Gauge Tank Volume Changes

MarineLink.com
Monday, March 24, 2014
This diagram shows the LVDT level sensor attached to the side of a tank using a flat-hook assembly. The high-permeability core follows the position of the stainless-steel float. The LVDT electronics sense the core position using magnetic induction. Output is a 4 to 20-mA instrumentation current loop corresponding to the position of the core in the LVDT body.

Configured with a float, Macro Sensors HSIR Series LVDT Linear Position Transmitters are serving as level sensors to measure liquid level changes from a few inches to several feet in gauging tank level volumes.

In this LVDT level sensor configuration, a stainless-steel float coupled to a nonmagnetic stainless-steel rod is attached to the high-permeability, armature core of the LVDT. The 4 to 20-mA loop-powered LVDT position transmitter senses the position of the core and, therefore, the level of the float. Sensitivity to the change in level depends on the length of LVDT. While LVDT level sensors are used to measure level changes from 0 to 2, 12, or 20 in. (50, 300, or 500 mm), shorter lengths offer greatest sensitivity.

In operation, as water level changes, the float moves up or down, raising the LVDT core along with it. A threaded stainless-steel rod, that protrudes from the other end of the core, carries two jam nuts that are used to adjust the position sensor output at the desired low water level. The nuts also prevent the core from falling out of the LVDT housing if the liquid level drops too low. A nonmagnetic clamp block attaches the stainless-steel body of the LVDT to a flat hook. The hook hangs the level-sensor assembly over the tank edge.

Core position is sensed using magnetic induction. Electronics of the LVDT are hermetically sealed inside a stainless-steel housing for protection against water and other environmental elements. A Teflon liner inside the bore minimizes any friction to core motion. As there are no springs to fatigue or parts to wear out, the LVDT Linear Position Sensors are nearly friction free to offer infinite resolution and long term operation.

macrosensors.com
 

Maritime Reporter August 2014 Digital Edition
FREE Maritime Reporter Subscription
Latest Maritime News    rss feeds

Marine Equipment

Tankship-specific Version of FindaportCD Released

Harbour & terminal information providers, Shipping Guides Ltd, says its latest tanker-specific  addition enables customers to access the most comprehensive port

VIKING Steps Up Pace of Innovation at SMM

This year’s SMM in Hamburg will see VIKING release more innovations than at any other point in its 50-year history, including new developments in PPE clothing,

RIMPAC Exercise Puts LCS Through Paces

It was the middle of May, and the littoral combat ship Independence was operating out of San Diego, testing components of the mine warfare mission package. The mission is one that,

 
 
Maritime Careers / Shipboard Positions Maritime Contracts Navigation Offshore Oil Pod Propulsion Port Authority Salvage Ship Repair Ship Simulators Winch
rss | archive | history | articles | privacy | terms and conditions | contributors | top maritime news | about us | copyright | maritime magazines
maritime security news | shipbuilding news | maritime industry | shipping news | maritime reporting | workboats news | ship design | maritime business

Time taken: 0.1529 sec (7 req/sec)