TSI Instruments DustTrak 8520 - Cleaning the 1.0 ΜM and 2.5 ΜM Inlet Conditioners

Maintenance
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Note: Negative mass concentration readings are an indication that
the D
USTTRAK monitor needs to be re-zeroed. The negative
reading of –0.001 in step 5 above is the only time when a
negative reading is acceptable.
Figure 4–1: Zero Checking the D
USTTRAK Aerosol Monitor
6. Press and hold the CALIBRATE key and wait for the displayed
countdown to reach 0, then immediately release the key. The message
“CALIBRATE ZERO” is displayed… if not, try again.
7. Press the SAMPLE key and wait for the 60-second countdown. When
the countdown is completed, the current calibration constant will be
displayed.
8. Press the CALIBRATE key again to return to survey mode. The re-
zeroing process is now completed.
Cleaning the 1.0 µm and 2.5 µm Inlet Conditioners
1. Turn the D
USTTRAK monitor off.
2. Remove the inlet nozzle and impactor plate.
3. Wipe the old grease and other residue off from the impactor plate and
nozzle. Once the nozzle and impactor plate are removed from the
D
USTTRAK monitor, compressed air can be used to blow them off. Do
not blow directly into the D
USTTRAK inlet. You can use isopropanol
or soap and water to clean the parts, but be sure they are dry before
reassembly.
4. Inspect the inlet for residue and clean as necessary.
5. Reapply grease to the impactor plate.
6. Reassemble the inlet conditioners.