BM Engineering’s guide to selecting the ideal level transmitter

BM Engineering are leading exponents of level transmitters from Bürkert Fluid Control Systems. PIF spoke to BM Engineering to get their expert opinion on some of their market leading level transmitters, as well as gaining some handy advice about how to select the best level transmitter for your application.

Level transmitters are basically an instrument that provide continuous level measurement, and can be used to determine the level of a given liquid or bulk-solid at any given time. Most of BM Engineering’s level transmitters are for continuous level measurement within a specified range and determine the exact amount of substance in a certain place. In contrast, point-level sensors simply indicate whether the substance is above or below the sensing point.

BM Engineering’s top rated level transmitters

Radar level transmitters

These highly accurate level transmitters work with high-frequency radar pulses that are emitted by an antenna and reflected from the product surface. The time of flight of the reflected radar pulse is directly proportionate to the distance travelled. If the tank geometry is known, the level can be calculated from this variable.

The Bürkert Type 8136 is a non-contact radar level transmitter for continuous level measurement. The unit is available in two versions with encapsulated horn antenna: one particularly suitable for level measurement of aggressive liquids in small vessels and the other for flow measurement in open flumes or gauge measurement in waters.

Ultrasonic level transmitters

Ultrasonic measurement is based on the time-of-flight principle. A sensor emits ultrasonic pulses which the surface of the medium reflects and the sensor detects again. The required time of flight is a measure for the distance travelled in the empty part of the tank. This value is deducted from the overall height of the tank to yield the level.

The Bürkert Type 8176 is a non-contact ultrasonic level transmitter, designed for continuous level measurement in open or closed vessels. The unit is suitable for liquids, but also for solids, in virtually all industries, particularly in water and waste water management.

How to select a level transmitter?

There are many variables that affect the process of selecting the optimal level transmitter for industrial and commercial processes. The selection criteria normally include physical considerations, including:

• Phase (liquid, solid or slurry)
• Temperature
• Pressure or vacuum
• Chemistry
• Dielectric constant of medium • Density (specific gravity) of medium
• Agitation (action)
• Acoustical or electrical noise
• Vibration or mechanical shock
• Tank size and shape

Just as important are application constraints, such as:

• Price, accuracy and response rate
• Ease of calibration or programming
• Physical size and mounting of the instrument
• Monitoring or control of continuous or discrete (point) levels.

BM Engineering can guide you through the complete selection process, and help you to find the perfect level transmitter to suit your specific application. Speak to BM Engineering Supplies today about their complete range of Level Transmitters by calling 0141 762 0657 or email [email protected].