HYDROTIDE II replaces the extremely successful HYDROTIDE unit, and is manufactured by RBR in Canada. It incorporates all of the same features, including on site user calibration that made the original system so popular. But with added features such as user replaceable batteries, external power option, simple telemetry interface, Windows software, increased memory capacity and a wave processing option.

 Changes in pressure due to changes in head of water are detected by a semiconductor strain gauge transducer.  These changes are recorded at pre-set intervals within the data loggers solid state memory.  The pressure transducer is manufactured from titanium and stainless steel and suitable for long term immersion in most liquids.  The transducer is connected to the logger via a single small diameter cable which also contains a micro bore pipe and thus allows atmospheric pressure to be applied to the rear of the transducers diaphragm automatically.  This provides accurate and calibration free compensation for changes in ambient atmospheric pressure.

 The HYDROTIDE II data logger is housed within a rugged, water tight aluminium enclosure.  Connections are made via water tight connectors.  Power is provided by four standard alkaline C cells in water tight holders.  This provides sufficient power to operate the unit for up to five  years.  The user has a wide selection of sampling regimes which are preset into the logger using simple Windows software.  The instrument may store up to 2,400,000 readings in its 8 MB flash memory. The HYDROTIDE II data logger is programmed to make a number of samples at 4Hz, by averaging these over an operator selectable averaging period, wave motion is filtered out.  The average depth value in metres is recorded and time/date stamped.  Corrections for water density can be applied by calibrating in situ if required.  Calibration constants are stored within the logger, and field calibration can be undertaken without deadweight testers by using the calibration constants provided with each sensor.

 The Windows software allows loggers to be set up and data downloaded and viewed as a simple graph.  Once downloaded, data may be archived to disk, printed as a time series, graphed, or exported to spread sheets and data bases.

 HYDROTIDE II is supplied complete with 1 bar (10 metre) pressure transducer with 15 metres vented cable, data cable, software, operating manual and aluminium transit case. Other ranges and cable lengths on request.

SPECIFICATIONS:-

Sensor:                         Semiconductor strain gauge with atmospheric venting via pipe in cable 

Range:                          0 - 10m with automatic atmospheric compensation as standard (other ranges to order)   

Accuracy:                     Overall system accuracy (linearity, hysterisis etc) typ 0.1% FS.  0.06% F.S option 

Resolution:                    <0.001% F.S 

Clock Accuracy:             +/- 32 seconds per year 

Update period :              Selectable in 1 second intervals from 10 seconds to 100 hours 

Averaging period :          Selectable in second increments (each sample 0.75 seconds approx.) 

Memory:                       8MB Flash 2,400,000 records (averaged values) 

Power supply:                4 off C size Alkaline batteries 

External Power:             12V 5mA (sample) 20 uA sleep 

Battery endurance:         5 years typ 

Communications:           RS-232  /485 to PC or telemetry 

Download speed:           Cable:- 115,000 samples/minute 

Construction:                 IP 65 aluminium case with venting membrane 

Dimensions:                  148mm x 75mm x 250mm  

Weight:                         (logger) 1.5 kg

Software: