3M 3MTM Marine Instruments User Manual


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Toxic and Carbon Dioxide Span Calibration
Toperformaspancalibrationwithaspecictoxicgas,pleasereferencethetoxicgas
table. For the CO
2
span calibration, the range (or span) should be a sizeable fraction of the
selected full scale range of the gas.
; NOTE: The range for the CO
2
sensor is 0 to 5,000 ppm. For a span calibration, it is recommended
to span cal to the value you will be measuring (i.e., 2,000 ppm).
1. Connect the appropriate gas, regulator, tubing and cal cap to the EVM.
2.Followsteps2-4above(inToxicZeroCalibrationsection)butselectSpan softkey in
step 3. (NOTE: For Oxygen span calibration, the typical span is 20.9%.)
Logging Toxic Gases or Carbon Dioxide
1. From the Start screen or any Measurement screen, press key.
• Toviewgasmeasurements,selecteithertheGasorCompositescreens
(by pressing from the start screen when Setup is selected.)
2. Press key to stop logging. (See “Viewing logged results” to access past sessions.)
Particulate advanced calibration (Gravimetric filtering)
Gravimetric Calibration Overview
(1)Reset the gravimetric and volume accumulators; (2) Insert a new (sealed) gravimetric
cassette;(3)Measureinthespeciclocationforapproximatelyfourtoeighthours;(4)
Notatethevaluedisplayedinthegravimetricaccumulatoreld(displayedintheparticulate
screen. (This value is used in conjunction with the weight of the measured dust in the
cassette.);(5)Removethegravimetriccassetteandweighthelteredcontents.(Typically,
sent to a lab for results.); (6) To determine the correction factor, calculate the ratio between
theparticulatemassvalueandtheweightfromthegravimetriclterlabanalysis.
Measuring particulates
1. From the start screen or any measurement screen, press the key. (Prior to
logging, a 5 second count-down appears.)
2. Press key to end the logged session. (See “Viewing logged results” to view past
sessions.)
Toxic (CO)
value
Run Icon
Composite
Measurement screen
CO
2
value
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