Flush capacitive ceramic pressure sensor for measuring corrosive and viscous liquid level from levels 0.4 metres of water up to 200 mH2O. This screw-in fluid level transmitter features high overload rating up to 50x and options for all plastic wetted parts.
Product Parameters
- Pressure Ranges: from 400 mmH2O up to 200 mH2O WC
- Accuracy: 0.35% FS or optional improved to 0.25% FS (IEC60770)
- Output Signals: 4-20mA or 0-10V dc
- Electrical Connections: DIN plug, M12 Binder or plus integral cable options with IP67 or IP68 protection
- Internal Wetted Seals: FKM, EPDM or FFKM
- Pressure Connector: G1 1/2 DIN3852 male thread with flush diaphragm
- Special Features: Low range and high overpressure, robust and chemically inert diaphragm
- Special Options: PVDF housing for aggressive chemicals, ATEX approved for intrinsic safety
Product Description
The LMK351 high abrasion resistant level sensor incorporates ceramic capacitance diaphragm technology which exhibits high accuracy and over-pressure at low liquid levels.
The capacitive aluminium oxide (Al2O3) ceramic sensing diaphragm of the LMK351 chemical level sensor is highly resistant to abrasive materials and corrosive chemicals such as acids and alkalines. For chemicals that are not compatible with stainless steel 316Ti there is the option for PVDF screw-in fittings.
For installations where frequent external washdown of storage tanks and equipment is required an IP68 cable gland can be selected for the LMK351 aggressive media level transmitter to make it waterproof.
A liquid level range from 1.3 up to 656 feet of water column can be specified for the LMK351 low range chemical level sensor with measurement accuracy of ±0.35 or 0.25% full scale.
For hazardous areas with volatile gases or dust present the LMK351 chemical level sensor has optional ATEX approved intrinsically safe electronics for use with IS barriers.
Product Applications
20% concentrated Sulfuric acid
Measuring the hydrostatic pressure of sulfuric acid at a concentration of 20%.
- SKU ID: s1-lmk351-76-51556
- Pressure Range: 0…0.25 bar
- Units: bar
- Reference Type: Gauge / Vented (atm to +P)
- Output Signal: 4-20mA (2 wire)
- Accuracy: 0.35% FS
- Electrical Connection: DIN43650A plug IP65
- Process Connection: G1 1/2 male DIN3852 with flush diaphragm
- Process Connector Material: PVDF (25bar and below only)
- Diaphragm Material: Ceramic Alumina Al2O3 99.9%
Sewage wastewater with sodium hypochlorite
Monitor the level of a sewage wastewater batch tank with a mild sodium hypochlorite solution.
- SKU ID: s1-lmk351-0006
- Part No: 471-2000-3-3-TR0-M00-1-B-2-000
- Pressure Range: 2
- Units: mH2O
- Reference Type: Gauge / Vented (atm to +P)
- Output Signal: 0-10V (3 wire)
- Accuracy: 0.35% FS
- Electrical Connection: IP68 (temp immersion) seal with 2m of cable
- Process Connection: G1 1/2 male DIN3852 with flush diaphragm
- Process Connector Material: Stainless steel 316L
- Diaphragm Material: Ceramic Alumina Al2O3 96%
- Media Exposed Seals: FKM
Reagent level measurement
Measuring the level of reagent in IBC containers.
- SKU ID: s1-lmk351-0001
- Part No: 470-1600-1-3-TA0-M00-3-B-2-000
- Pressure Range: 0 to 0.16
- Units: bar
- Reference Type: Gauge / Vented (atm to +P)
- Output Signal: 4-20mA (2 wire)
- Accuracy: 0.35% FS
- Electrical Connection: IP67 seal with 2m of cable
- Process Connection: G1 1/2 male DIN3852 with flush diaphragm
- Process Connector Material: PVDF (25bar & below only)
- Diaphragm Material: Ceramic Alumina Al2O3 96%
- Media Exposed Seals: EPDM
Wet scrubber slurry level
Monitor the level of slurry used in a wet scrubber to control air pollution.
- SKU ID: s1-lmk351-0002
- Part No: 471-1600-1-3-TAO-M00-7-B-2-000
- Pressure Range: 1.6 mH2O g (5.25 ftH2O g)
- Output Signal: 4-20mA (2 wire)
- Electrical Connection: Cable gland IP67
- Length of Cable (metres) if required: 2
- O-Ring Material: FFKM
- Pressure Connection Material: PVDF
- ATEX IS Approval (4-20mA output only): Yes
- Ceramic Diaphragm Material: Alumina 96%
- Accuracy: 0.35% FS
Perc (Perchloroethylene / Tetrachloroethylene)
Measure the level of perc (perchloroethylene/tetrachloroethylene) which is a solvent commonly used in dry cleaning processes and metal degreasing operations.
- SKU ID: s1-lmk351-0005
- Part No: 471-0500-1-3-100-M00-1-1-2-000
- Pressure Range: 0.5
- Units: mH2O
- Reference Type: Gauge / Vented (atm to +P)
- Output Signal: 4-20mA (2 wire)
- Accuracy: 0.35% FS
- Electrical Connection: DIN43650A plug IP65
- Process Connection: G1 1/2 male DIN3852 with flush diaphragm
- Process Connector Material: Stainless steel 316L
- Diaphragm Material: Ceramic Alumina Al2O3 96%
- Media Exposed Seals: FKM
Product Help
Re-orientating DIN plug electrical connection
We have to put an LMK 351 unit in a built in construction for one of our customers, and i have a question about the DIN plug electrical connection. Is it possible to rotate the electrical connection when the main 1 1/2 inch thread is screwed on the tank, or to put it another way, is it possible to rotate the plug independently of the main thread?
We do not recommend trying to re-orientate the male part of the connector, which is permanently mounted on the sensor, since it may lead to damage of the wiring inside.
Instead we suggest removing the mating part of the connector and extract the wiring block from inside the outer case, and then replacing it in a different orientation. This will allow you to re-orientate the cable exit from the DIN plug connector by 90, 180 or 270 degrees.
25% Sulfuric acid at ambient temperature
We need a hydrostatic level pressure transmitter to measure a process solution which is 25% sulfuric acid over a range of 0 to 100 inches of water. This is an outdoor application so the ambient temperature is -15 to +100 degrees F.
We would suggest the following LMK351 configuration with PVDF port material and FKM seals:
- SKU ID: s1-lmk351-0003
- Pressure Range: 0 to 100
- Units: inH2O
- Reference Type: Gauge / Vented (atm to +P)
- Output Signal: 4-20mA (2 wire)
- Accuracy: 0.35% FS
- Electrical Connection: DIN43650A plug IP65
- Process Connection: G1 1/2 male DIN3852 with flush diaphragm
- Process Connector Material: PVDF (25bar & below only)
- Diaphragm Material: Ceramic Alumina Al2O3 96%
- Media Exposed Seals: FKM
Gas pressure measurement
Do you know if this product is suitable to measure pressure in systems containing gases?
Primarily the LMK351 is used to measure hydrostatic pressure of liquids in order to determine the liquid level, but it can also be used to measure the pressure of liquids and gases as well.
Sulfuric acid 60% conc @60°C
I have a tank filled with a Sulfuric acid (60-65 %), the temperature is around 60-65 degree Celsius, and the pressure is 40psi (max). Can I use the LMK 351 sensor?
Yes, but we would suggest the following configuration which includes the optional PVDF process connector and FKM seals:
- SKU ID: s1-lmk351-0004
- Pressure Range: 40
- Units: psi
- Reference Type: Gauge / Vented (atm to +P)
- Output Signal: 0-10V (3 wire)
- Accuracy: 0.35% FS
- Electrical Connection: DIN43650A plug IP65
- Process Connection: G1 1/2 male DIN3852 with flush diaphragm
- Process Connector Material: PVDF (25bar & below only)
- Diaphragm Material: Ceramic Alumina Al2O3 96%
- Media Exposed Seals: FKM
Related Documents
Specification data sheet
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