water quality monitor - sensor check procedures

Water Quality MonitorSensor Check Procedures

©2014 Sea-Bird Scientific Inc.

Overview

•Check procedures for each sensor• Pre-deployment• Post deployment• Tracking

•Service intervals• Tracking can reinforce


WQM – Optics

• ECO Flntu or Triplet • Stability tests over time shown largest change in response in first year• +/- 2% of full scale

• Routine checks done pre and post deployment capture potential drift

• Bio-wiper™/Triplet wiper prevents bio-fouling from forming over optics• Service is ESSENTIAL • Every 13 months of in-water use


WQM – Optics Pre-deployment Checks:Establishing the ECO Offsets

• Procedure based on standard ECO offset/dark count FAQ • Cover LED and Detector with black electrical tape and turn system

on• Be sure to smooth tape to remove bubbles

• Record the output for all channels• Use minimum or average value as offset• WET Labs records 60 seconds of data at 1 Hz – reports minimum value as

offset on calibration sheet• Record new values under the Troubleshooting Tab on WQM Host


WQM – Optics Pre-deployment Checks:Updating the ECO Offsets

•WQM Host 1.51• Under Advanced drop down

menu • Setup External Data Port• Select Internal ECO

• Click boxes to enter new offsets

• Using terminal program • Exit to C prompt • $xit

• c:> set chl.off


• No specialized equipment required• Saturation stick • Hand• Calibration Cap

•With sensor running, start with target 6-8” away and gradually move closer to face of sensor• Counts should increase, goal is full saturation (4120 counts) • Move away to ensure counts fall back to stable in air values

WQM – Optics Pre-deployment Checks:Establishing the ECO Saturates


•Verify functionality•Track instrument changes over time•Additional supplies:• 12 oz can Diet Coke• 500 ml bottled water/DI water• 1000 ml glass beaker• Stir stick

WQM – Optics Pre-deployment Checks:Performing Mid-Point Characterization Checks


•NTU Test Procedure:• Point ECO into space, record counts as offset value• Cover face of the sensor with calibration cap or hand• Record raw counts – maximum and minimum• If offset, maximum or minimum change exceeds 50 counts –

contact WET Labs Support

WQM – Optics Pre-deployment Checks:Mid-Point Characterization Checks Cont.


•Chlorophyll Test Procedure: •Mix Diet Coke with bottled/DI water • Allow to degas

• Point ECO into space, record counts as offset value• Immerse ECO end into test fixture to test solution• Record raw counts• If change in offset or chlorophyll raw counts

exceeds 50 counts from previous test – contact WET Labs Support

WQM – Optics Pre-deployment Checks:Mid-Point Characterization Checks Cont.


WQM – Conductivity Pre-Deployment Check

•Check conductivity zero frequency against calibration sheet • Rinse cell with distilled/DI water• Dry cell should read very close to zero conductivity reading on

calibration sheet• If not, cell may be dirty/damaged

• Attempt cleaning with Triton X solution


•More difficult to check of all sensor components• Requires moving water to make accurate reading

• Plug plumbing with water inside tubing – submerge in aerated or stable water• Let sit for ½ hour or few hours• Take reading• Should give near saturation value if operating properly• 98% or 101%

• DO saturation level will jump when/if pump is turned on

WQM – Conductivity Pre-Deployment Check


WQM – Temperature Pre-Deployment Check

•Comparison to secondary sensor

•Known temperature comparison


WQM – Pressure Pre-Deployment Check

•Check responsiveness with finger over pressure sensor•Reset Pressure Offset from Host Program• Pre-Deployment drop down menu• Reset the WQM Pressure Offset


WQM – BLIS Pre-Deployment Check

• Fill bleach intake port with DI water• Under Help dropdown

menu choose Troubleshooting• Select BLIS• Run 100 BLIS Cycles

• Run 2-3 times to fully empty


WQM – Sensor Validation

• Validation of moored data set with CTD cast as available• Allows for corrections• Winkler comparisons for DO sensors• Field calibrations for chlorophyll

• Run through pre-deployment sensor checks to verify functionality• Pre package cleaning for base line• Post package cleaning

Questions?Please feel free to contact our Customer Support Team at

+1 541 929 5650.

water quality monitor - sensor check procedures

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