Switches Indicators & Gauges

Guided Microwave level transmitters are designed for continuous level measurement.

They have a very versatile range of applications and are suitable for use in both liquid (including corrosive liquids) and solid products. Even conditions such as steam generation, density fluctuations and changes of the dielectric constant do not influence the accuracy of the measurement. This is because the microwave principle that the transmitter is based on works independently to the products characteristics (e.g. moisture, intense dust/noise generation density, temperature, overpressure, foal, dielectric value and the shape of the material cone).

The simple installation and the 2 wire electrical connection make guided microwave level transmitters one of the most popular level instruments on the market.

Guided Microwave level transmitters are used in the following industries (although not limited to only these industries): chemical, pharmaceutical, oil and gas, food, dairy, beverage, paper, automotive, aggregates, steel, water and waste water and marine.

How it works

Guided Microwave level transmitter operate based on the TDR (Time Domain Reflectometry) principle. High frequency microwaves/micropulses are sent along a steel rod or cable at the speed of light. When these microwaves reach the product surface pulses are reflected and received by the base. The time it takes for the microwaves to fit the product surface is evaluated by the base and converted to a distance.

Where do I get one?

Semrad Pty Ltd is a leading Australian distributor of level switches and transmitters, designed specifically for harsh industrial applications, including caustic and chemical solutions. They produce and distribute a range of guided microwave level transmitters. For more information or to place an order click here to view their website.

Bulksolids Flow Sensor is a microwave based non-contact solids flow sensor. It utilizes the Doppler Effect to detect the movement of solid materials (such as powders and granules) in pneumatic pipelines. These sensors are very low cost and reliable which makes them ideal for monitoring the flow of bulk solids in vacuum pipelines, ducts, air slides, gravity chutes, feeders and at transfer points in vibrating chutes, conveyer belts and bucket elevators.

The sensor has wide variety of applications in a range of industries such as the Cement Making, Iron Making (Blast Furnace), Agriculture and Food processing industries.

Functionality

The sensing head transmits microwaves toward the target material. A section of the microwaves are reflected back to the head which contains a sensor. The sensor analyses whether the microwaves are from a moving or stationary object. The highly-penetrable microwave passes through a buildup on the head and even through pipe made of non-conducting materials such as plastics.

Features

• Minimally affected by dirt and other non-metallic material on the sensing head, steam and airborne particles.
• Can be used in high temperature and high pressure
• Can detect hazardous materials.
• Mounted flush, no intrusion or damage to material flow.
• Built-in amplifier enables easy installation and wiring; lightweight and compact.

The NivoCONT is a contact style level switch which is based on the conductivity principle. The NivoCONT is primarily design for use in liquids for pump control.

How they work:

The NivoCONT contains probes which are immersed into the tank. These probes work as contacts for an electric circuit. A connection is then established between the probes and the conductive liquid. This connection is converted to an output signal.  The length of the probe should be proportional to the size of the tank and the level that is being detected. When the probe is no longer submerged it triggers a response to indicate that the tank level is too low. Up to four separate probes can be placed within the tank depending on the model to enable for detection at several different levels.

Advantages:

• Contains no moving parts (i.e. it has a high reliability rating and does not break easily).
• Self cleaning (i.e. low maintenance).
• Contains flexible cable extensions of up to 20 meters (ideal for use in larger tanks).

A range of NivoCONT products can be purchase from Samrad (a switch and levels distributor). For more information click here to see what Samrad have to offer you.