The Burkert 573599 Type 8188 is a guided microwave level transmitter designed for continuous level measurement of liquids. With a measuring range up to 75 m, it is well-suited for tall vessels. It is insensitive to dust and steam, and process conditions such as strong steam generation, density fluctuations, or changes in dielectric constant do not influence the measurement accuracy. Build-up or condensation on the probe or vessel wall also do not affect the measuring result. It is capable of liquid interface measurement, typically an oil/water interface.

Measuring Principle

High frequency microwave pulses are guided along a steel cable, a rod, or a coaxial cable. Upon reaching the product surface, the microwave pulses are reflected and received by the processing electronics. The running time is evaluated by the instrument and outputted as distance. Time-consuming adjustment with the medium is not necessary.

For interface measurement, a part of the microwave impulses is reflected upon reaching the product surface. The other part passes through the upper product and is reflected by the interface. The running times to the two product layers are processed by the instrument.

General Technical Data

Feature	Specification
Measured quantity	Level of liquids
Measurement deviation	±2 mm (According to DIN EN 60770-1)
Measuring cycle time	<500 ms
Step response time	≤3 s
Operating voltage	9.6...35 V DC (without display/configuration module)
Output	4...20 mA/HART
Process connection	Thread G or NPT: 3/4, 1
Electrical connection	Cable gland M20 × 1.5
Degree of protection	IP66/IP67 with cable plug mounted and tightened

Probe Variants

Variant with Rod Probe

• Probe: Rod-∅ 8 mm in stainless steel 316L (1.4404 or 1.4435)
• Probe length: 0.3...6 m (lateral load: 10 Nm)
• Process temperature: -40...+80 °C (up to 6 bar) / -40...+150 °C (up to 40 bar)
• Process pressure: -1...+6 bar (PPS connection) / -1...+40 bar (PEEK connection)
• Dielectric constant: εr > 1.6

Variant with Cable Probe and Gravity Weight

• Probe: Cable-∅ 4 mm with gravity weight in stainless steel 316L
• Probe length: 0.5...75 m (max. tensile load: 2.5 KN)
• Process temperature: -40...+80 °C (up to 6 bar) / -40...+150 °C (up to 40 bar)
• Process pressure: -1...+6 bar (PPS connection) / -1...+40 bar (PEEK connection)
• Dielectric constant: εr > 1.6

Variant with Coaxial Probe

• Probe: Coaxial-∅ 21.3 mm (tube) in stainless steel 316L
• Probe length: 0.3...6 m (lateral load: 60 Nm)
• Process temperature: -40...+150 °C
• Process pressure: -1...+40 bar
• Dielectric constant: εr > 1.4

Mounting Instructions

During operation, the probe must not touch any installations or the vessel wall. If necessary, fasten the probe end. In vessels with a conical bottom, it can be advantageous to mount the sensor in the center of the vessel, as measurement is then possible nearly down to the lowest point of the bottom.

Do not mount the instruments in or above the filling stream. Make sure that you detect the product surface, not the inflowing product.

WARNING

The housing must not be used to screw the instrument in! Applying tightening force can damage internal parts of the housing. On instruments with process fitting thread, the hexagon must be tightened with a suitable screwdriver.

Dimensions

Variant with Rod Probe

Variant with Cable Probe and Gravity Weight

Variant with Coaxial Probe