Sensors & Transducers


Detecting the interface between sludge and water

July 2015 Sensors & Transducers

An important requirement in the operation of sewerage, wastewater and water treatment works is to find the interface or location of the high solids region of a settlement tank and the lower solids region above.

Detecting the presence of the sludge at a fixed level is one of the simplest ways of carrying out this control measurement. The sensors are installed, thru-beam mode with the transmitter and receiver aligned opposite of each other (for accurate detection), at a certain height and when the sludge reaches it, an alarm is raised. The alarm can be used to stop a pump, change the position of the bell mouth, divert the flow or call an operator to the site to investigate the problem.

The Telco Sensors series MPA 21 is a 2-channel, multiplexed photoelectric amplifier, which is to be used in conjunction with two sets of remote transmitters (LT) and receivers (LR). The series offers a choice between two individual relays or two individual NPN/PNP transistor outputs, with or without an adjustable 0-3 sec on/off time delay.

Use of a dual channel system allows the user to have a two stage control process, which can for example control a pump at the first level and an alarm/stop at a higher level avoiding overflow.

The two channels operate independently of each other with their own set of remote transmitter and receiver. The multiplexing function ensures that cross talk between channels is prevented. Telco’s infrared remote sensors LT and LR are unaffected by alignment, contamination and build up on the face of the sensor and are IP67 making for easy installation for a hassle free application.



Credit(s)



Share this article:
Share via emailShare via LinkedInPrint this page

Further reading:

Smart alternative for float switches
ifm - South Africa Sensors & Transducers
With the LI level sensor, you can reliably detect leakages and point levels on a permanent basis. The capacitive measuring system has no moving parts. Malfunction or maintenance issues due to deposits on the mechanical parts are therefore eliminated.

Read more...
Telco sensors in the pulp and paper industry
Gail Norton Instrumentation Sensors & Transducers
The pulp and paper industry poses a major problem for most photoelectric sensors. The high level of contamination in these dusty, dirty and grimy environments makes it impossible for most competing sensors to operate and sense reliably and efficiently.

Read more...
Precision acoustic imagers
Comtest Sensors & Transducers
To help users identify and localise ‘mechanical areas of interest’ within short timeframes, Comtest has added a unique new feature to Fluke’s ii910 precision acoustic imagers.

Read more...
Efficiency and precision with IO-Link sensors
RS South Africa Sensors & Transducers
RS South Africa has its own brand known as RS PRO, which offers a choice of over 88 000 products across all industries and technologies. The guaranteed quality and breadth of this range make RS PRO the smart choice for your business.

Read more...
Smart alternative for float switches
ifm - South Africa Sensors & Transducers
With the LI level sensor, you can reliably detect leakages and point levels on a permanent basis. The capacitive measuring system has no moving parts. Malfunction or maintenance issues due to deposits on the mechanical parts are therefore eliminated.

Read more...
Optical fork sensor series
Gail Norton Instrumentation Sensors & Transducers
The OFS series consists of self-contained optical fork sensors that are housed in a durable, U-shaped aluminum housing, which operates in through-beam mode.

Read more...
In-line process transmitter to optimise sterile processes
WIKA Instruments Sensors & Transducers
The new model DMSU22SA in-line process transmitter from WIKA helps to optimise sterile processes in the pharmaceutical and food industries, with less energy consumption, less cleaning effort ,and more safety.

Read more...
Automated clean-in-place
Endress+Hauser South Africa Sensors & Transducers
A clean-in-place (CIP) process is integral to a food and beverage producer’s responsibility to deliver safe, high-quality products to consumers. However, as industries worldwide shift focus towards sustainability, CIP procedures face new challenges.

Read more...
Signal conditioning is the protective armour between plant and field
Omniflex Remote Monitoring Specialists Sensors & Transducers
Measurement and control of physical properties are the foundation of all critical industrial technologies. Ian Loudon, international sales and marketing manager at remote monitoring specialist, Omniflex explains the challenges of industrial signal conditioning and the importance of safety engineering.

Read more...
Precise detection of complex rotational movements
Beckhoff Automation Sensors & Transducers
The EP3751-0260 EtherCAT Box module by Beckhoff connects an acceleration sensor with an inertial measurement unit - a gyroscope. This provides accurate detection of acceleration and rotational motion in addition to shock, vibration and tilt measurement, both as preprocessed values and as raw sensor data.

Read more...