3M 3MTM 用户手册

Particulate Zero Calibration

Prior to calibrating, ensure the impactors are well-greased with an applied thin-film of silicone

grease.  (Please see “Impactor Care” on page 10 or EVM series user manual.)
1.  Attach the Zero/HEPA filter and tubing into the turret. Rotate the turret to PM.

2.  Select Calibration from the Start screen and select PM (using up/down arrows).

3.  Press Cal softkey and then press Start softkey.  Once level is stabilized, press Set softkey.

4.  Once level has been set, you can press Save or Cancel.  (Please refer to Chapter 4 of 

     EVM series manual for more information.)  

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NOTE: Once saved, the instrument will apply the zero calibration to all profiles. The zero calibration is

           stored in the History screen and a calibration. Verify can be performed (to ensure no drifting). 

Particulate Advanced Calibration (Gravimetric)

  

(1)Reset the gravimetric and volume accumulators; (2) Insert a new (sealed) gravimetric cassette;  (3) 

Measure in the specific location for approximately four to eight hours; (4) Record the value displayed in

the gravimetric accumulator field 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 

filtered contents. (Typically, send 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 filter lab analysis. (Ratio = true

weight/EVM gravimetric displayed value).   (7) Enter user correction value (Setup\Particulate screen.  Select 

profile field and then press Edit softkey. Add Factor using up/down arrows. Press On/OFF/Esc key twice to

return to start screen.) 

Logging Particulates

1.  Before logging particulates, ensure the impactors are clean and well-greased.

2.  From the start screen or any measurement screen, press        key.   

3.  Press        key to end the logged session.  (See “Viewing logged results” to access past   

     sessions.)

Used for particulate zero cal. 

Insert tubing into the impactor of the 

labeled “2.5” vent opening  

Turn the turret so “PM” appears on the 

display of the EVM.