LMP307 Submersible Level Transmitter

LMP307 Submersible Level Transmitter

Submersible level transmitter for measuring liquid level with a 4-20mA current loop or a 0-10V voltage output plus optional ATEX approval for intrinsically safe use in hazardous areas in ranges from 1mH2O up to 250mH2O.

Product Parameters

  • Hydrostatic Level Ranges: from 1mH2O to 250mH2O gauge
  • Accuracy: 0.35% full scale with optional 0.25% or 0.1% IEC60770
  • Output Signal: 4-20mA or 0-10Vdc, optional ATEX/IECEx and SIL2
  • Electrical Connections: Submersible PVC, PUR or FEP cable with IP68 ingress protection
  • Pressure Connection: Protective self draining nose cone
  • Media Compatibility: Stainless steel 316Ti body, stainless steel 316L diaphragm, FKM seal gasket plus selected cable jacket
  • Dimensions: 27mm dia
  • Weight: 200 g without cable
  • Special Options: ATEX and IECEx approved for intrinsic safety, IP66 cable termination enclosure (4-20mA, 2wire only), SIL2 electronics, temperature measurement

Product Description

The LMP 307 submersible level transmitter is a general purpose sensor for measuring the level of fresh water or other mildly corrosive liquids.

The LMP-307 submersible level transmitter can be used to measure the water level in reservoirs, lakes, open flow channels & weirs and groundwater level of boreholes.

Relatively low water levels can be measured with the LMP307 submersible level transmitter despite its 27mm diameter. This is possible by incorporating a highly sensitive miniature silicon diaphragm with a very thin isolation membrane back filled with silicone oil.

Product Applications

Deep well pump shut off

Monitoring level of water above a deep well pump to determine pump shut off point.

  • SKU ID: s1-lmp307-0004
  • Part No: 451-4001-1-1-1-1-3-2-040-000
  • Sensor Type: Level only
  • Level Sensing Range: 0 to 40
  • Units: mH2O
  • Reference Type: Gauge / Vented (atm to +P)
  • Output Signal: 4-20mA, 2 wire
  • Accuracy: 0.35%FS above, 0.5% FS below 4mH2O (11-12bit res)
  • Installation Type: Submersible probe with removable nose cone
  • Housing Material: Stainless Steel 316L
  • Diaphragm Material: Stainless Steel 316L
  • Media Exposed Seals: FKM
  • Cable Type: PUR (70degC max)
  • Cable Length: 50
  • Cable Length Units: Metre (m)

Yacht grey water tank

Measure the level of grey water tank which holds waste water from a yacht’s galley sink, shower, washing machine and dish washer.

  • SKU ID: s1-lmp307-0001
  • Part No: 451-1000-1-1-1-1-5-2-003-000
  • Sensor Type: Level only
  • Level Sensing Range: 0 to 1
  • Units: mH2O
  • Reference Type: Gauge / Vented (atm to +P)
  • Output Signal: 4-20mA, 2 wire
  • Accuracy: 0.35%FS above, 0.5% FS below 4mH2O (11-12bit res)
  • Installation Type: Submersible probe with removable nose cone
  • Housing Material: Stainless Steel 316L
  • Diaphragm Material: Stainless Steel 316L
  • Media Exposed Seals: FKM
  • Cable Type: PUR (70degC max)
  • Cable Length: 3
  • Cable Length Units: Metres (m)

Product Help

2m diesel tank level with 2mm resolution

I am looking for a tank level transmitter for measuring diesel level up to 2 metres and I want to detect a 2mm change in level, what product do you suggest?

An LMP307 submersible level transmitter with this specification would provide a 4-20mA output signal with a 14 bit resolution (0.12mm) and 0.1% full scale accuracy (2mm).

Greywater compatibility

Is the LMP307 submersible water level transmitter compatible with greywater?

Yes the LMP307 is compatible with greywater and it is recommended to install the probe with the nose cone removed to prevent blockage.

ATEX approval

Does the LMP307 submersible level probe meet ATEX Class 1 Zone 2 requirements?

The LMP307 exceeds the requirements. Class 1 is not used as part of the European ATEX markings, but is most likely taken from the USA markings where Class 1 corresponds to a Gas environment approval. Zone 2 refers to the ATEX classification for Explosive atmosphere which maybe present during exceptional conditions for a short period of time.

The ATEX markings for the LMP307 are II 1 G Ex ia IIC T4 Ga, which is suitable for use in Gas Zone 0 which is a higher safety risk environment.

ATEX 1/21

I am looking to install a water level sensor in a tunnel running below a river and the area is rated at ATEX 1/21. I would like to know if the LMP307 would be suitable for this application.

Yes the LMP307 is ATEX approved for zone 0 hazardous gas environments or zone 20 hazardous dust environments which is a higher rating than zone 1/21.

Calibration out of the water

How do I calibrate the LMP307 submersible pressure transmitter when it is out of the water?

Like many submersible pressure transmitters used for water level measurement, a process connection is not necessary and can actually be detrimental to precise measurement, due to trapped air.

Removing LMP307 submersible pressure transmitter nose cone

In order to calibrate the LMP307 out of the water, first you must prise off the nose cone to reveal the flush diaphragm underneath.

Removing protective cap from LMP or LMK submersible pressure sensor

Then using the clamping fixture, the LMP307 can be sealed inside the metal cylindrical part, with an elastomer seal, by tightening the clamping part down onto the backend of the sensor around the cable exit. Care should be taken not to overtighten the wing nuts otherwise too much stress maybe applied to the front end sensing element. The assembly is now ready to be connected to a suitable pressure calibrator for testing.

LMP307 Calibration Adaptor DSC_0013

High temperature diesel fuel level to 2m

Would I be able to use the LMP307 for measuring the level of high temperature Diesel fuel immersed a 2 metre high tank?

Yes the LMP307 has the option for FEP cable which is resistant to Diesel fuel, and the capability to measure lower range level such as a 2m depth fuel tank. The maximum operating temperature range for the LMP307 is 70 degC.  If the temperature is higher than this then we would suggest the LMK382 instead with TPE cable, which is designed to tolerate up to 125°C.

Max measurement depth

What is the maximum measuring range in meters for the LMP307?

The maximum depth range is 250 metres.

Related Documents

LMP307 specification data sheet

LMP307T specification data sheet

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