Guided Wave Radar Level Meter
The basic principle of Guided wave radar is time travel, radar wave runs at the speed of light, running time can be transformed into level signal by electronic parts.Probe sends out high-frequency pulse and transmits along the cable probe or rod probe, when the pulse get material surface it will be reflected by the receiver inside the instrument, and the distance signal is transformed into level signal.
APPLICATION
Guided wave radar level meter used in water tank, acid and alkali storage tank, the slurry storage tank, solid particles and small oil tanks.
All kinds of conductive, non conductive medium, and corrosive medium.Such as coal, ash storehouse, oil tank, acid tank, etc.
TECHINICAL PARAMETER
DRUL-971 Cable Type
Application | liquid, powder, solid particle |
Measurement range | 30m |
Process Connection | thread, flange |
Medium Temperature | -40...250℃ |
Process Pressure | -1.0...20bar |
Accuracy | ±10mm |
Frequency Range | 100MHz...1.8GHZ |
Explosion-proof/ Protection Degree | ExiallCT6/IP67 |
Signal Output | 4...20mAHART(two-wire) |
DRUL-972 Rod Type
Application | liquid, powder, solid particle |
Measurement range | 6m |
Process Connection | thread, flange |
Medium Temperature | -40...250℃ |
Process Pressure | -1.0...20bar |
Accuracy | ±10mm |
Frequency Range | 100MHz...1.8GHZ |
Explosion-proof/ Protection Degree | ExiallCT6/IP67 |
Signal Output | 4...20mAHART(two-wire) |
DRUL-973 Coaxial Rod Type
Application | liquid, powder, solid particle |
Measurement range | 6m |
Process Connection | whorl, flange |
Medium Temperature | -40...250℃ |
Process Pressure | -1.0...20bar |
Accuracy | ±10mm |
Frequency Range | 100MHz...1.8GHZ |
Explosion-proof/ Protection Degree | ExiallCT6/IP67 |
Signal Output | 4...20mAHART(two-wire) |
Installation Method
• Reasonable installation can ensure the instrument long-time use and accurate measure.
The instrument can adopt tread connection. Thread length can’t exceed 150mm. It can also be installed on the short pipe. If the diameter of the short pipe is from 2″to 6″, the height of the short pipe should ≤150mm. If it is installed on a longer short pipe, the cable probe should be fixed on the bottom in order to avoid the contact with the end of the short pipe.
• The installation of DN200 or DN250 in a short pipe
When the instrument is installed in a short pipe which diameter is longer than 200mm, the inside wall of the short pipe will generate an echo. Measurement errors will be caused when the dielectric constant is low. Therefore,for diameter 200mm or 25mm short pipe , a special flange with ‘horn interface’ needs to be chosen.
• Installation on the plastic tank
Attention.
If you want the instrument operates normally, the surface of the process connection must be metal. When the instrument is installed on the plastic tank, if the top of the tank is also plastic or other non-conductive material, the instrument must match metal flanges. If you adopt thread connection, a metal plate should be equipped.
• The distance between the instrument probe and the tank wall
The distance from the instrument probe to the tank wall is recommended to be 1/6-1/4 of the tank diameter.(Longer than 300mm at least. For the concrete tank, 400mm at least.) When you choose the length of the probe, pay attention that the distance from the bottom of the probe to the tank bottom is longer than 30mm.
Notes:
• The radar installation can’t be installed to the spout below
• Avoid other devices in the tank contacting with the microwave conductive part.
• Avoid the guided wave cable probe contacting the installation short pipe.
The downward pull that the cable suffers
When you feed and out-feed, the medium will produce downward pull to the cable probe. The strength of it depends on the following factors:
1.the length of the cable
2.the density of the material
3.the diameter of the silo
4.the diameter of the cable
The following is the pressure produced by a 6mm cable probe in typical medium.
The optimization of the interference
• The inhibition of the interference echo:
The software can realize the inhibition of the interference echo. Then achieve the ideal measurement.
• Bypass pipe and guide wave pipe(It applies to liquid only.) For the medium whose viscosity ≤500cst, can use bypass pipe, waveguide or coaxial rod radar can be used to avoid the interference.
Measurement of corrosive medium
• When you measure the corrosive medium, you can choose the rod probe with plastic or tetrafluoroethylene pipe
The fix of the end of the guided wave radar probe
• There are 2 ways to fix the end of the probe. One is insulation fix and the other is non-insulation fix.
• Insulation fix: When the dielectric constant is low and the probe is fixed on the bottom of the metal tank, the insulation fix is needed.
• Non-insulation fix: When the dielectric constant is high and the tank is made of metal, other material with low dielectric constant or the similar dielectric constant to the medium, the non-insulation fix is chosen.
• Remark: When the user doesn’t know it is insulation or non-insulation, please contact with our company
The relationship between different kinds of medium and the measurement distance is listed in the following diagram.
Medium group | DK(s) | Solid particle | Liquid | Measurement range |
1 | 1.4 …1.6 |
| -condensensing gas, for example,N2C02 | 3m (Only refers to the coaxial rod probe.) |
2 | 1.6-1.9 | -Plastic with particles | -Liquefied petroleum gas, such as propane | 25m |
- lime stone, special cement | -solvent | |||
- sugar | - Freon 12 / Leone | |||
| -Palm oil | |||
3 | 1.9…2.5 | -ordinarycement, plaster | -mineral oil, fuel | 30m |
4 | 2.5 …4 | - Grains, seeds | -Benzene, styrene, tolunene, | 30m |
- Stone | - furan | |||
- Grit | - naphthalene | |||
5 | 4...7 | -wetstone, ore | -Chlorobenzene, chloroform | 30m |
-salt | -cellulosespray | |||
| Isocyanuric hydrochloride , the amine | |||
6 | >7 | - Metal powders | -aqueous liquids-alcohol | 30m |
- Carbon black | -liquid ammonia | |||
- Coal |
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company
Yantai dongrun Instrument Co., Ltd. founded in 1998. It specializes in manufacturing online water quality analyzer, level meters, pressure gauge, flow meter, special temperature gauge and laboratory water analyzer.. Our company cooperates with Chinese Academy of Sciences and builds up a water analysis laboratory, mainly producing TOC analyzer, ammonia analyzer, fluorescence oxygen analyzer, etc. We have passed the ISO9001 certification. Our professional R & D team can provide technical supports to satisfy customer demand and our unique technologies can meet different working conditions.
We are the important supplier of Yantai Wanhua Group,Pepsi,Sinopec,Jereil etc.