tender for the purchase of multi water quality parameters go through the quotation request , the hydrolab multiparameters for marine application should be a portable, intelligent water quality instrument and sensors options include conductivity, optical dissolved oxygen ( do ) , ph / orp, turbidity, nitrate, chlorophyll, and temperature. with 4 smart sensor ports which permit interchangeability and / or replacement by the users in the field. all data should be displayed in a single display.the water quality instrument must include sensor screw tool for easy replacement or change of smart sensors under normal operating conditions and to prevent premature damage of any of the smart sensors under normal operating conditions.sensor description:barometric sensor should sensor range shall be 300 – 1100 mbars with accuracy of ± 3 mbar and resolution 0.01 mbar, ambient temperature: temperature range should be -20° to +70°c with accuracy of ±2°c and resolution of 0.1°c, optical dissolved oxygen sensor – smart sensorthe optical do sensor shall comply with epa-approved should measurefrom 0 to 60 mg / lshould have accuracy of 0.1mg / l of reading from 20 to 60 mg / l. resolution: 0.01mg / l, conductivity sensor should measure range:0-350ms / cm t, ds : 0-350ppt, salinity350psu, accurcay should have ± 0.5% & resolution , the conductivity sensor should have report measurements as: actual conductivity ( μs / cm, ms / cm ) , specific conductivity ( μs / cm, ms / cm ) , salinity ( psu, ppt ) , total dissolved solids ( tds ) ( ppt, ppm ) , resistivity ( ohms-cm ) , and density ( g / cm3 ) , display: it should be built-in lcd screen in itself to provide clear, instant visual indicators of overall readiness, sensor status, power voltage, and connectivity. also want titanium sensor guard to avoid corrosion. communicate connections: should have the ability to communicate wirelessly through bluetooth wireless technology. also, it should be able to log data directly to windows / android / mac devices. the system must be able to record live reading when connected to a cable, wireless bluetooth display and based on windows / android / apple devices with the application.accuracy: ±0.1 ph unit.minimum orp range: ±1400 mv. orp sensor accuracy:±5.0 mv