OTT ecoLog 500 Water Level Logger

OTT ecoLog 500 Water Level Logger



Water level sensor with built-in datalogger for surface and groundwater applications

The OTT ecoLog 500 is a complete system for water level and temperature measurement. Designed for full deployment inside groundwater wells as well as surface water applications, the OTT ecoLog 500 offers data and alarm message transmission options via SMS, HTTP, FTP and e-mail, giving users flexible remote data access from their office.
  • Surface water, Groundwater
  • Vented pressure cell
  • Waterlevel/Pressure, Water temperature
  • Measures, stores, and transmits water level and temperature data
  • 0 … 4, 10, 20, 40, and 100 m
  • ± 0.05% FS
  • Yes


  • Remote data transmission: receive data, status messages, and low power warnings from the office via SMS, FTP, HTTP, and e-mail, eliminating field visits for data download and troubleshooting
  • Complete in-well solution: all components are inserted into the groundwater well, eliminating the possibility of instrument vandalism
  • Battery life: up to 10 years with lithium batteries, alkaline options are also available. All batteries are field-replaceable without additional tools
  • Long-term durability: a robust ceramic pressure cell, kevlar-reinforced cable, and high-quality 904 L stainless steel housing provide lasting quality
  • User-friendly interaction: only one program required to setup unit and download data, plus a simple infrared communication interface that provides easy on-site data download


Water level measurement  
Measuring ranges 0 … 4 m, 10 m, 20 m, 40 m, 100 m
Pressure resolution 0.01 % FS
Pressure accuracy ±0.05 % FS
Long-term stability ±0.1 % / year FS
Temperature measurement  
Measuring range ?-25 °C … +70 °C
Temperature resolution 0.1 °C
Temperature accuracy ± 0.5 °C; higher accuracy optionally available
Electrical data  
Power supply 2 x 1.5 V C Alkaline cells or Lithium cells, 3.6 V/13 Ah or Lithium cells, 3.6 V/26 Ah
Battery life @ 1 h measurement interval & one transmission per week  
Lithium-battery (DD): approx. 10 years
Alkaline batteries (CC): approx. 2 years
Modem GSM Standard 850/900/1800/1900 MHz, GSM (quad band), GPRS
Antenna Built-in, weather-proof, external antenna optionally available
Interface at site Infrared (IrDA)
Memory 4 MB, approx. 500,000 measured values
Sampling/storage interval 5 seconds …? 24 hours
Installation ≥ 2″
Environmental conditions  
Operating temperature -30 °C …? + 85 °C
Storage temperature -40 °C …? + 85 °C
Dimensions L x Ø  
Communication unit 522 mm x 50 mm
Probe 195 mm x 22 mm
System length  
(Cable length incl. communication unit and pressure probe) 2 … 200 m ± 0.25 m
Communication unit Aluminium, PA-GF
Sonde Stainless steel (DIN 1.4539, 904 L )
Communication unit (w/o. batteries) approx. 0.720 kg
Probe approx. 0.300 kg
Type of protection  
Communication unit IP67
Probe IP68
EMC limits According to EG 204/108/EG, ETSI EN 301 486-1/-7, EN 61326-1 FCC approved