We are looking for a level sensor for measuring from 0 to 100 millimetres of water height, in an ebb and flow horticulture hydroponic system used in greenhouses and indoor farms. We need an accuracy of at least 1 mm height. The measurement and control system will accept a 0-10 volt signal input. The water contains nutrients such as nitrogen, potassium and phosphorus, plus pieces of soil, growing medium and algae. The sensor will be immersed in the ebb and flow tray which will be 0 to 10 centimetres deep.
We would suggest the LMK 382 submersible low range water level sensor. The minimum possible range is 0 to 400 mm, but although you would only be using 25% of the range, it will still achieve the level of accuracy you require. If using the 0-10V output, you will get 0 – 2.5V out at 0 – 100mm measurement. The accuracy is better than 0.25% of 400mm, so you can expect it to be accurate to 1mm. The LMK 382 has a removable nose cone which will reveal a flush diaphragm. So if you install it without the nose cone this will prevent any clogging of the sensor from soil and plant material, and make it easy to remove any build up over time.
LMK382 Low Range Water Level Sensor
- SKU ID: s1-lmk382-46-27039
- Pressure Range: 0 to 400
- Units: mmH2O
- Reference Type: Gauge / Vented (atm to +P)
- Output Signal: 0-10Vdc, 3 wire
- Accuracy: 0.25% FS
- Installation Type: Probe version with flush diaphragm and detachable nose cone
- Housing Material: Stainless Steel 316L
- Diaphragm Material: Ceramic Al2O3 99.9%
- Media Exposed Seals: FKM
- Cable Type: PUR (70degC max)
- Cable Length: 5
- Cable Length Units: Metres (m)