Kaidi KD-902F High Frequency Radar Level Transmitter Wave Radar Solid Level Sensor Guided Radar Signal Level Meter

1.  Product  Principle

The radar water level antenna emits extremely narrow microwave pulses that travel at the speed of light, and part of the energy is reflected back when it encounters the surface of the measured medium and is received by the same antenna. The time interval between the transmitted pulse and the received pulse is proportional to the distance from the antenna to the surface of the measuring medium. Due to the extremely high propagation speed of electromagnetic waves, the time interval between the transmitted pulse and the received pulse is very small (nanosecond order) and it is difficult to confirm. The high-frequency radar water level gauge uses a special demodulation technology that can accurately identify the transmitted pulse and the received pulse The distance between the antenna and the surface of the measured medium can be further calculated.

      A    Range set

      B    Low adjustment

      C    High adjustment

Datum measurement:  Screw thread bottom or the sealing surface of the flange.

Note: Make sure the radar level meter the highest level cannot enter the measuring blind area (Figure D shown below).

• Application characteristics

The radar water level gauge uses a 26GHz transmitting frequency and has: 

Ø Small beam angle, concentrated energy, stronger anti-interference ability, greatly improved measurement accuracy

Ø The antenna is small in size, easy to install, and easy to add dust cover and other antenna protection devices

Ø Lighter weight, about 1KG, easy to install

Ø The maximum measurement range can reach 70 meters, which can cover water level measurement such as large reservoirs

Ø With a variety of output circuit interface and data acquisition system.

   Ø The pulse working mode, radar level meter transmit power is very low, no harm to human body and environment.

2. Product  Introduction 

902F

3. The  Installation Requirements

 Installation Precautions:

Please pay attention to the following items to ensure that the meter can be installed correctly:

Please reserve enough space for installation.

Please avoid installation situations with strong vibration.

Dragon door frame installation

Flange installation

• Gauges are installed at 1/4 or 1/6 of the diameter of the tank.

• The minimum distance from the pipe wall is 200 mm.

• Avoid installation in the center of the tank.

  
  

Typical installation errors：

Ø Conical tank

The instrument cannot be installed above the inlet. 

Note: Sun-shading and rain-proof measures should be taken during outdoor installation..                      

         ①Correct  ②Error  rainproof measures

Ø The meter cannot be installed in the middle of the top of an arched or round tank. In addition to producing indirect echoes, it will also be affected by multiple echoes. Multiple echoes may be larger than the signal threshold of true echoes, because multiple echoes can be concentrated through the top, so they cannot be installed in the center.

                                                                                                                                        ①Correct                         ②Error

Ø When there are obstacles in the tank that affect the measurement, it is necessary to install a reflector to measure normally

                                                                                                                         ①Correct                                       ②Error

• Container takeover requirement

Make sure that the antenna extends into the tank at least 10mm away.

4. The Electrical Connection  

• The power supply voltage:

• Cable Connection

• Connection  mode

Ø  The Modbus-RS485 wiring diagram as follows:

 Ø 24V  2-wire wiring diagram as follows:

 Safety  instructions:

Ø Please observe the local electrical code requirements!

Ø Please comply with local requirements for personnel health and safety regulations.

    All electrical components of instrument operation must be completed by the formal training of professionals.

Ø Please check the instrument nameplate to provide product specifications meet your requirements. Please make sure that the power supply voltage and instrument nameplate on the requirements.

 Protection  grade:

This instrument meets the protection class IP66/67 requirements, please ensure the waterproof cable sealing head. The following diagram:

     How to install to meet the requirements of IP67:

     Please make sure that the sealing head is not damaged.

     Please make sure that the cable is not damaged.

     Please make sure that the cable for use with electrical connection specification.

     Cable into the electrical interface before its curved downward, ensure that the water will not flow into the shell, see the①

     Tighten the cable seal head, see the②

     Please electrical interface will not use blind plug tight, see the③

5. Instrument Commissioning

There are two kinds of debugging method:

1) Display / Button (With split display, you need to debug on the split)

2) Debug through computer software 

Display /  Button: 

Debug the meter through the 4 buttons on the display screen. The debugging menu has four languages to choose from. The measured value can be read very clearly through the glass window.

Display / Button  

                                                                                                 ① Liquid crystal display(LCD)

                                                                                                 ② Adjust by button

 PC software debugging:

Connected to PC by HART

                                                                                   ① USB interface   ②  Radar level meter    ③  HART converter    ④  250 Ω Resistor

 HART  handheld  programmer:

                                                                                   ① HART handheld programmer    ②  Radar level meter    ③  250 Ω Resistor

6. Structure Size   (Unit: mm)

The Outer Covering:

Cast aluminum shell

Plastic shell

Product  size:

Gantry frame size:

Flange  type:

7. Technical Parameters

8.   Meter  Linearity

902F

The launch angle depends on the antenna size

-Φ76mm                        12°

Precision                      See chart

9. Product  Model  Selection

902F