Although many materials will last a long time in salt-water because the erosion rates are very low; when a thin piece of material such as a pressure transducer diaphragm is exposed to a corrosive media even a low erosion level will lead to a short operating life.
A typical material used for manufacturing pressure sensor diaphragms is stainless steel but most grades apart from Duplex stainless steel do not offer adequate corrosion protection to maintain the integrity of thin diaphragms over a long period of time. Therefore other metals such as Hastelloy C276 and Titanium alloy which are very resilient to saltwater corrosion are used instead.
The Level Troll 500 water level data logger is compatible with brackish, tidal or sea-water. The level loggers outer casing is made from Titanium which has excellent long term protection against corrosion particularly with saline liquids.
The Level-Troll 500 Titanium level logger relies on a silicon piezo-resistive sensing element for measuring the hydrostatic pressure which is contained within an oil filled capsule which has a thin Titanium isolation membrane. The small cross sectional area of the silicon chip allows an 18.3mm diameter Titanium capsule to be used in the loggers construction so that the LevelTroll 500 water logger can measure the water level in narrow boreholes for geotechnical surveys of groundwater.
The Level-Troll500 liquid level logger combines a Titanium pressure transducer with an accuracy of ±0.05% FS, a battery with a life of 5 years and a data logging memory of 1MB into one compact submersible level measurement package which can be lowered into position without any need for any electrical connection to the surface if necessary.
For gauge referenced level measurements the Level Troll 500 water level logger has a vented cable which is supplied with desiccant caps to prevent moisture entering into the electronics.
Alternatively an absolute reference pressure sensor can be specified eliminating any need for a vented cable. A number of installations measuring absolute pressure can be compensated for changing atmospheric pressures by including one BaroTroll barometric pressure data logger at each location. The software supplied with the LevelTroll500 ground-water level logger will automatically synchronise the level measurements with the corresponding atmospheric pressure measurements to record the true liquid level. The LevelTroll500 water logger can also record the liquid temperature simultaneously with the level readings.
tel: +44 (0)844 800 9440
©2013 SensorsONE Ltd, all rights reserved.