WD81

1.1 Features

 A more compact RF architecture, a higher signal-to-noise ratio, and a smaller blind zone arerealized based on the self-developed Complementary Metal-Oxide-Semiconductor (CMOS)millimeter wave Radio Frequency (RF) chip.

 No fear of attenuation of radar echoes by vapour and dust.

 Stable measurements for substances with weak reflective properties or low dielectric constants.

 5GHz working bandwidth allowing for higher measurement resolution and accuracy.

 A minimum antenna beam angle of 3°. The interference in the installation environment has lessimpact on the instrument, making it easier to install and more suitable for mixing conditions.

 Shorter wavelength. It yields better reflection properties on solid surfaces, and it significantlyreduces the reliance on universal flanges.

 Support for remote setting up and remote upgrade. It reduces waiting time and increases workefficiency.

 Support for Bluetooth setting up on mobile phones for easy maintenance by field personnel.

You can set up the instrument on site via the LCD or on the PC via the software. You can achieve thecommunication between the 80GHz radar level meter series of products and the PC through thefollowing ways:

 USB to RS485 serial cable in 4-wire system.

 USB to TTL serial cable in 2-wire system.

 USB to Hart-modem in 2-wire system.

 Set up via Bluetooth on mobile phones. It makes on-site setting up safer and more convenient.

 4G network for remote setting up via remote modules.

Note: The measurement blind spot depends on the antenna selected and the reflective propertiesof the object to be measured. Laboratory

blind spot tests are based on water or metal plates.

Pay attention to the following points during installation:

 For liquid applications, try to ensure that the mounting flange is parallel to the liquid surface sothat the transmitted electromagnetic wave is incident perpendicular to the liquid surface.

 For solid applications, you can suitably relax the installation angle. If the material accumulationangle is relatively large and the blind spot

that is required to measure is relatively small, it isrecommended to use a universal structure to adjust the transmitting direction to be nearlyvertical to the inclined material surface.

During installing, try to avoid interfering objects within the radar beam range, such as mixing blades, protrusions and other objects. Interfering objects can easily generate interference signals and affectthe normal operation of the radar.

See below for typical working conditions:

 Keep the antenna beam range free of any interference, such as ladders and steps:

 Avoid the contact between antenna beam and feeding inlet:

 At least 20cm away from the vessel wall when mounting to avoid incorrect readings:

 Conical vessels that wish to monitor the complete loading and unloading process require the useof a gimbaled flange to ensure that the

beam is directed to the bottom of the vessel as far aspossible, otherwise measurements at the bottom of the vessel may be inaccurate, as

shown inFigure 4-4. If the bottom material level is negligible, there is no need to use a gimbaledstructure.

5.1    4-wire product with 24 VDC supply in single cavity housing

In 4-wire applications, the 4-20mA analog output is 2 separate terminals, in addition to the 24vsupply terminal. The 4-wire system also

provides a 485 output terminal to connect to a PC for settingup or for sites where a 485 interface is required.

In 2-wire applications, in addition to the traditional 4-20mA output supply terminals, the instrumentalso has a serial communication terminal

to connect to the current mainstream IOT devices orpass-through devices for remote control and setting up

The 80 GHz radar level meter series of products perform level or liquid measurement tasksaccording to the settings. You can modify locally

via the Local Display Module (LDM). LDMconsists of 4 keys and a 128*64 dot matrix LCD.

LDM offers 4 interface modes. The 4 keys in different interface modes have different functions.

 Main interface displays system running status and current measurement result.

 Echo interface displays the real-time measured echo of the system.

 Setup interface sets various data parameters for system operation.

 Input interface enters the values, numbers or characters of parameters.

Figure 6-1 shows the main interface:

Table 6-1 describes the functions of the 4 keys in the main interface:

The parameters on the main interface are described as follows:

1. Real-time value. It indicates the result of the process quantity measured by the system in realtime, including level, height and distance. See

section 6.4.3 for display settings.

2. Damping value. It is the smooth output of the real time value through the damping filter. Seesection 6.5.1.7 for details.

3. Temperature. It indicates the internal circuit temperature of the instrument.

4. Version. It indicates the model number of the product customized by you.

5. Communication status. It indicates the heartbeat of the system. It blinks once every secondmeaning that the instrument is working

properly. If it does not blink or blinks only once in along time, the communication is abnormal.

6. Unit. It indicates the system measurement units. See section 6.4.3 for detailed settings.

7. Current. It indicates the ideal 4-20mA current output value corresponding to the analog quantityto be measured. It is obtained according to the Low/High calibration points and Currentfunction. See section 6.5.1.4 and 6.5.2.6 for detailed conversion relations.

8. Error code. See Appendix A for detailed definitions.

In the main interface, press ESC key to enter the echo interface. Figure 6-2 shows the echo interface:

Table 6-2 describes the functions of the 4 keys in the echo interface:

The parameters on the main interface are described as follows:

1. Echo strength. It indicates the maximum echo intensity in the measurement range. For a metalplate at 10m, the echo intensity should be at

least 80dB.

2. Echo amplitude. It indicates the information on the intensity of the radar-selected echoindicated by the black arrow. A good metal reflector should have around 90dB echo strength.Ifthe echo strength is less than 30dB, it indicates a weak echo signal. It is required that a technician to carry out the appropriate troubleshooting.

3. Echo SNR. It indicates the information on the difference between Echo amplitude andthreshold curve.

4. Echo position. The arrows in the echo interface are divided into 2 types: hollow and solid. Hollow indicates the radar's real-time selected

echo position, while solid indicates the radar'sfinal output selected echo position. The number following this arrow is unaffected by the

Sensormode setting and always gives distance information, pointing to the selected echo crest. Normally the two arrows overlap to form a

black arrow, but in the event of strong interference orsudden movement of the target, the solid black and white arrows may become separated. This isnormal.

5. Range set value.

In the main interface, press ENT key to enter the setup interface. Figure 6-3 shows the setupinterface:

Table 6-3 describes the functions of the 4 keys in the setup interface:

Basic menu contains the necessary functions required for the normal operation of the instrument. Ingeneral operating conditions, you can set

these parameters to enable a quick start-up of theinstrument. Select Basic and press ENT key to enter the options interface. Table 6-4 shows

the list ofoptions:

Select Advanced and press ENT key to enter the options interface. The advanced settings are bestoperated by a professional who is more

familiar with the working principles of radar. Table 6-5shows the list of options:

Display menu can realize the switching between Distance units, Temperature units and Displaylanguage. Table 6-7 shows the list of options:

Diagnosis menu can realize the statistics of historical data and summarize the characteristics ofworking conditions. Select Diagnosis and press ENT key to enter the options interface. Table 6-6shows the list of options:

Information interface tracks the product information of the instrument, such as sensor model, serialnumber, and other information. Select

Information and press ENT key to enter the options interface. Table 6-8 shows the list of options:

6.5.1   Basic

The basic settings allow for a quick start-up of the instrument.

Note:

 Unless explicitly stated, default settings are indicated with an asterisk (*).

 Unless explicitly stated, the entered parameters in all position-related settings of the instrumentare distance information. It is the distance from the sensor to the material/liquid level, forexample, Low/High calibration point.

6.5.1.1.Application type

The 80GHz radar series of instruments integrate an adaptive algorithm for solid and liquidapplication. You can configure the instruments

according to the actual measurement object on site. After configuration, the Vessel type and Material type menus are automatically adjusted. Figure 6-4shows the Application type interface:

6.5.1.2.Vessel type

Vessel type has a variety of radar operating modes to suit different on-site applications. At the sametime, it provides customer-friendly

demonstration modes for in-field tests. Table 6-9 describes thedetails of Vessel type:

6.5.1.3.Material type/Dielectric constant

Different substances to be measured generates different echo characteristics. You can set a widerange of built-in substance type options in the instrument. The Material type affects the echoselection and the correct setting enables the measurement to be more accurate and stable.

When you switches the Application type option, the Material type option is automatically switched. Table 6-10 describes the specific

parameters:

6.5.1.4.Low/High calibration point

In Low/High calibration point, the high level corresponds to the full material position and the lowlevel corresponds to the empty position.

Low level - high level = DCS system range. Low/Highcalibration point map the corresponding relationship between the measured value and

the currentoutput (4-20mA). Figure 6-7 shows the Low/High calibration point interface and definitions:

For example:

The vessel to be measured is 5m high; then the High calibration point is set to 0m, the Lowcalibration point is set to 5m. The input number is the distance from radar to the specified point

6.5.1.5.Near range

The Near Range and the Far Range setting together determine the valid area of echo that can beidentified by the algorithm. The algorithm

ignores echoes within the blind spot. You can use thisoption to avoid the interference from the near end and prevent material level from

jumping to 100%as well.

6.5.1.6. Far range

The range defines the operating area of the algorithm and does not refer to the remote measurementlimits of the instrument or the range of

the DCS system.

The algorithm ignores echoes-m that are outside the range when processing. Setting the rangeappropriately can avoid multiple reflective

interference and possible interference signals that are outof range. The range should be 1-2m greater than the actual vessel height, especially

for vessels with aconical bottom, so that the instrument can obtain the full echo characteristics. Figure 6-9 shows theFar range interface:

6.5.1.7.Damping

Damping smooths out the sudden changes in measurement results, and reflects more accurateaverage positions. Figure 6-10 shows the Damping interface and a smoothing result:

Table 6-11 describes the details of Damping:

6.5.1.8.Sensor mode

Figure 6-11 shows the Sensor mode interface:

Sensor mode only changes the type of the real-time value and damping value displayed in the maininterface, and does not change the type of

current output from the instrument. To change the current output type, see Current function. Table 6-12 describes the calculation method for the

level, distance and space:

6.5.2.1.False echo learning

False Echo learning can block interference echoes caused by interfering objects in the vessel andform a background screening curve, which is threshold curve TVT. This option contains 2 levels ofguidance menus, False echo range and False echo mode. There are 3 methods that can be selectedin False echo mode:

 Full range. It indicates that false echo learning is performed within the default full range of theinstrument.

 Range include. It indicates that false echo learning is performed only within the set range.

 Range exclude . It indicates that false echo learning is performed only outside the set range.

After selecting Range include or Range exclude, further enter the range Start and End points. Figure 6-12 shows the menu interfaces:

For example:

In working conditions if there is an interference signal within 2m-4m range from the instrument, youneed to create a new TVT curve to

suppress the interference. To create a new TVT curve, followthese steps:

1. Select Range include in False echo mode.

2. Set the Start to 2m and the End to 4m in False echo range.

3. Select New in False echo learning. Confirm and wait for the OK prompt to pop up. Thisindicates that you have successfully created a new

TVT curve.

Figure 6-13 shows the principle and effect of false echo learning. The learned false echo curve isperfectly overlaid on top of the real-time

measurement curve, so that you can only see the truematerial level echoes. You can observe through the echo interface or analyze more fully

on the hostcomputer.

Table 6-13 describes the other meanings under different combinations of options:Note: A Time Varying Threshold (TVT) hovers above

the echo profile to screen out unwantedreflections (false echoes). In most cases the material echo is the only one which rises above

thedefault TVT.

6.5.2.2.Factory reset

Factory reset restores the default factory settings of the instrument. The recovery time is about 30s. After the reset, the system jumps to

Main interface automatically. You are recommended to use thisoption first when the instrument does not measure properly due to improper

operations.Figure 6-14 shows the Factory reset interface:

6.5.2.3.Fill/Empty rate

Fill/Empty rate adjusts the response rate of the instrument to the actual material level. When the fillrate setting is changed, the response rate is automatically changed. Figure 6-15 shows the Fill/Emptyrate interface:

6.5.2.4.mA simulation

mA simulation enables the loop current to output a specific current value fixedly for checking thatthe 4-20mA output loop current is accurate and normal. Figure 6-16 shows the mA simulationinterface:

6.5.2.5.4mA/20mA setpoint

4mA setpoint is the 0% point of the analog quantity. 20mA setpoint is the 100% point of the analogquantity. You can customize the

4mA/20mA setpoint based on the actual needs. This setting has ahigher priority than Low/High calibration. The system outputs the

analog current at the end basedon this setting.

Note: It is not recommended that you set this option individually. You only need to set the Low/Highcalibration.

Figure 6-17 shows the 4mA/20mA setpoint interface:

6.5.2.6.Current function

Current function decides whether 4-20mA or 20-4mA is output on the bus. Figure 6-18 shows thecurrent function interface:

For example:

The vessel to be measured is 5m high; then the high level is set to 0 and the low level is set to 5. Ifthe current output function selects the level,

the empty vessel current outputs 4mA, full vesseloutputs 20mA. If the current output function selects the space, the empty vessel current

outputs20mA, full vessel outputs 4mA.

Figure 6-19 shows the corresponding relations of the loop output current and this option.

6.5.2.7.Bus address

According to the communication protocol supported by the instrument, set the specific Bus addressand incorporate the instrument into the

bus on site. Figure 6-20 shows the Bus address interface:

Table 6-14 describes the details of Bus address:

6.5.2.8.Distance offset

Distance offset corrects the reference point of the sensor. Figure 6-21 shows the Distance offsetinterface. The default reference point is

calibrated to the point ‘a’ shown in the figure, which is thelens tip. If you want to set reference point to point ‘b’, enter ‘h1’ in the

setting.

Table 6-15 describes the details of Distance offset:

6.5.2.9.Fail-safe mode

Fail-safe mode set the actual output current value when the level meter loses echoes. See AppendixA for detailed error code. Figure 6-22

shows the Fail-safe mode interface. The Keep option indicatesthat the output maintains the last valid measured current.

6.5.2.10. Fail-safe timer

Fail-safe timer is also known as lost of echo timer (LOE timer). When the duration of echo lossexceeds the set value of Fail-safe timer, the

4-20mA terminal outputs according to the set value ofFail-safe mode option, and the main interface displays 0001 error code. The default

value is 100sand the range is 0-1000s. Enter Advanced and select Fail-safe timer. Figure 6-23 shows theFail-safe timer interface:

6.5.2.11. Parameter backup

The ‘Read’ option backs up all the current configurations in the instrument to the display module. The ‘Write’ option sends the saved

configurations in display module to the current instrument.Theseoptions is designed for the operation of several similar vessels on site. You

can back up theparameters to the display module when setting up the radar for one vessel; then set up other similarvessels.

Figure 6-24 shows the Parameter backup interface:

6.5.3.1.Echo curve

See Echo Iinterface description.

6.5.3.2.False echo curve

You can view the false echo curves that have been generated.

6.5.3.3.Historical data

Historical data records the sensor measurement value based on the current Sensor mode, countswithin the Historical period, and draws curves. Figure 6-25 shows the Historical data interface:

Note: The right side displays the more recent data. The number in the upper left corner indicates themaximum value of the history

measurement. The number in the upper right corner indicates the setHistorical period. The maximum count is 360 hours, which is 15 days.

6.5.3.4.Historical period

See Historical data for the definition.

6.5.3.5.Historical maximum measurement

Historical maximum measurement counts the highest and lowest values of measurement resultsafter leaving the factory. The result type is

based on the Sensor type, such as level, distance, andspace. Enter Diagnostics menu, select Historical maximum measurement and select

Read to readthe lowest and highest historical measurement values.

Select Clean to clear the historical statistics, and then the system starts counting again. Figure 6-26shows the Historical maximum measurement interface:

6.5.3.6.Historical maximum temperature

Historical maximum temperature counts the highest and lowest values of the operatingtemperature on the core circuit board after leaving

the factory. See Historical maximummeasurement for operating instructions. Figure 6-27 shows the Historical maximum temperature

interface:

6.5.3.7.Historical fill rate

Historical fill rate counts the highest and lowest values of the fill rate after leaving the factory. SeeHistorical maximum measurement for

operating instructions. Figure 6-28 shows the Historical fillrate interface:

6.5.3.8.Historical empty rate

Historical empty rate counts the highest and lowest values of the empty rate after leaving thefactory. See Historical maximum measurement for operating instructions. Figure 6-29 shows theHistorical empty rate interface:

6.5.4.1.Sensor unit

Sensor unit determines the unit of the real-time value and damping value in measurement interface. The default unit is meters. Enter Display menu and select Sensor unit. Figure 6-30 shows theSensor unit interface:

6.5.4.2.Temperature unit

Temperature unit determines the unit of temperature in measurement interface. The default unitis ℃. Enter Display menu and select Temperature unit. Figure 6-31 shows the Temperature unitinterface:

6.5.4.3.Language

Language determines the display language of all interfaces to suit your needs. Currently Chineseand English are available. The default

language is Chinese. Enter Display menu and selectLanguage. Figure 6-32 shows the Language interface:

6.5.4.4.LCD contrast

LCD contrast adjusts the display contrast of LCD. The range is 0-127. The higher the value, thedarker the color displayed. Figure 6-33 shows

the LCD contrast interface:

6.5.4.5.Current percentage

Current percentage is a switch. When switched on, the main interface shows the percentage of theanalog quantity. Figure 6-34 shows the Current percentage interface:

6.5.5.1.Sensor model

Sensor model is the product model of the instrument. Select Sensor model and press ENT to enter. Figure 6-35 shows the Sensor model

interface:

6.5.5.2.S.N. (Serial number)

S.N. is the product serial number of the instrument. Select S.N. and press ENT to enter. Figure 6-36shows the S.N. interface:

6.5.5.3.Tag

Tag identifies different sensors in the filed. It contains 16 characters and you can set each characterto 0 ~ 9 or A to Z. Figure 6-37 shows the

Tag interface:

The following describes the instructions on how to use the keyboard, using the Near range setting asan example:

1. Press DN/down arrow to shift the cursor to the right. After moving right to the last position, thecursor returns to the far left. Figure 6-38

shows how the cursor shifts:

2. Press UP/up arrow to cycle the cursor from 0 to 9. Figure 6-39 shows how the cursor cycles:

3. Press ENT to complete the setting. The LCD returns to the confirmation status and you can seethe OK in the lower right corner of the

interface, meaning the setting is accomplished. Figure6-40 shows the interface when the setting is accomplished:

7.1 First-level menu tree

7.2 Secondary menu tree-basic settings

7.3 Secondary menu tree-Advanced

7.4 Secondary menu tree-diagnostics

7.5 Secondary menu tree-display

7.6 Secondary menu tree-information

Error code is displayed in the Measurement Interface as shown below

Beam Angle: Half power beam width. WD8X has 3°beam width and the divergence of the beam isonly ±2.6m at a distance of 100m.

Range resolution：It refers to the minimum distance that two objects can be distinguished by thelevel radar. WD8X has a 5.1GHz bandwidth,

and thus the ideal Range resolution=C/2B≈3cm

Measurement Accuracy: The minimum shift that can be distinguished by the level radar. WD8X'secho signal is analyzed by unique

algorithm, and the accuracy is 0.5mm.

Ambient temperature: The temperature of the surrounding air that comes in contact with theequipment.

Blind zone: the limitation of the level meter, that is to say, the radar cannot give the right measuredresult within Blind zone.

dB (decibel): A unit representing the amplitude of a signal.

Dielectric constant (DK): The ability of a dielectric to store electrical energy. The increase indielectric constant is directly proportional to the

increase in reflection amplitude. The dielectricconstant of air is 1.

Echo: A reflected signal with amplitude large enough to be distinguished from the transmitted signalby a certain method is called an echo.

False echo: Generally speaking, false echoes are generated by obstacles in the container or multiplereflection.

Multiple echoes: Multiple echoes due to multiple reflections between the radar and the target

Polarization: The properties of the emitted electromagnetic waves, describing the direction andamplitude of the electric field vector changes

over time.

Repeatability: The variance of multiple measurements of the same variable in the same situation.

Speed of light: The speed of electromagnetic waves in free space is 299,792,458 meters per second.