Liquid level monitoring for any container shape
April 2001
Sensors & Transducers
The liquid level sensing system from Trolex (Figure 1) can accurately monitor both the level and volume of the contents of any container, whatever its size and shape. It gives the customer the precise information needed to control liquid levels as required and the peace of mind of knowing exactly the volume or value of stock remaining. It operates by monitoring the pressure in the head of liquid and then linearising this result via the Trolex TX9044 programmable sensor controller in accordance with the tank shape – thus allowing the user to monitor the precise volume of liquid present in the tank at any time.
Figure 1. Volume determining system diagram
With storage tanks that are an irregular shape, whether by design or due to nonstandard usage, problems can often occur with ascertaining the exact volume of liquid inside them. The new 'intelligent' level system can overcome any such difficulties with its ability to interpret irregular patterns of volume change.
The Trolex system employs the accurate TX6114 pressure sensors (Figure 2). These units are built with a chemical and corrosion resistant housing and a ceramic diaphragm that is leak-proof and comes with an integral four active arm strain gauge. They are fully temperature compensated and have excellent linearity and long-term stability. They measure the gauge pressure of the head of liquid in the tanks and then relay the results to the TX9044 programmable sensor controller.
Figure 2. The TX6114 pressure sensor
The sensor controller then linearises the pressure input according to a preprogrammed look-up table (Figure 3) that represents the container in question, and displays the volume of the tank contents in engineering units.
The sensor controller can handle eight such inputs and has simultaneous display for all the channels. It has data communications and output ports for RS232 or RS485, as well as four output relays with adjustable setpoints, time delays, hysteresis, relay phase and latching.
Figure 3. A sample look-up table transfer function curve
The programmable sensor controllers can feed into a PC to provide consumption analysis, re-order levels, auto-fill and shutdown, and many other options. The system can also be expanded according to customer requirements to include temperature monitoring, flow monitoring, gas detection and any other parameter within the Trolex range.
Figure 4. Liquid level switches for both external and internal mounting
Trolex also manufacture a range of liquid level switches for both external and internal mounting on tanks, gearboxes, pressure vessels and boilers (Figure 4). These level switches are designed to comply with the exact requirements of the application, particularly with regard to number and position of switch contacts, process connections, materials of construction and type of electrical connection. They can also be fitted with either a temperature sensor or temperature switch.
Trolex SA
(011) 397 6958
[email protected]
www.trolex.com
Further reading:
Miniature inductive sensors
ifm - South Africa
Sensors & Transducers
The inductive IY/IZ type sensors from ifm are used in various industrial areas where space is limited.
Read more...
The expanding role of 3D cameras in industrial quality control
Sensors & Transducers
Across factory floors, warehouses, mines and research centres worldwide, computer vision paired with 3D camera technology is revolutionising quality control.
Read more...
PDS implementation on mines
Sensors & Transducers
Level 9 vehicle intervention for collision avoidance has been mandatory on South African mines since 2022, yet the effective roll-out of proximity detection systems remains slower than expected. This is not due to the technical limitations of integration but to operational readiness on site.
Read more...
Monitoring analogue process values
ifm - South Africa
Sensors & Transducers
Everywhere in industry, electronic sensors are used to detect process values such as temperature, pressure or flow. Process value monitoring often takes place directly in the sensor.
Read more...
Protecting buildings’ embodied carbon with retrofitted systems
Schneider Electric South Africa
Sensors & Transducers
The World Economic Forum has said that around 80% of the buildings in existence will still be around in 2050; it is therefore essential that in order to combat climate change we retrofit them for energy efficiency.
Read more...
Listening for damage to wind turbines
Sensors & Transducers
The Fraunhofer Institute for Integrated Circuits, working in concert with the Fraunhofer Institute for Wind Energy Systems, has developed a solution that can be used to identify cracks and breakage inside wind turbine blades remotely at an early stage.
Read more...
Enhancing gold leaching efficiency
Endress+Hauser South Africa
Sensors & Transducers
Endress+Hauser offers a range of advanced technologies designed to enhance the stability and accuracy of pH and dissolved oxygen measurements on gold processing plants.
Read more...
Powering safer mining with PDS
Sensors & Transducers
With the mining industry under increasing pressure to prioritise safety without compromising productivity, Booyco Electronics is pushing the boundaries of Proximity Detection System and Collision Avoidance System technology across both underground and surface operations.
Read more...
The car of the future listens
Sensors & Transducers
The perception of external sounds in cars has been lacking, even in automated driving. That is why Fraunhofer IDMT-HSA is researching the integration of acoustic sensor technology in its KI4BoardNet project with the Hearing Car.
Read more...
Telco Sensors for blocked or empty chute detection
Sensors & Transducers
In most industries there is a problem with photoelectric sensors as highly contaminated environments make it difficult to operate and sense reliably. Telco Sensors overcomes this through its powerful high-performance infrared sensors that ensure penetration of harsh pollution to guarantee reliable detection.
Read more...