Differences

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--- teom_1405df [2025/07/24 15:10] – rickbeil
+++ teom_1405df [2025/07/24 20:14] (current) – external edit 127.0.0.1
@@ Line 15: / Line 15: @@
 ===problem (Summer 2025)===
-Mass concentration wasn't being recorded in from the PM-10 size bin.
+Mass concentration wasn't being recorded in from the PM-10 size bin. Then later PM-2.5 was found to be giving inaccurate readings.
 ===Cause===
-There are two magnets that are within the mass transducer that allow for a weight to be measured from the mass transducer. These two magnets were not aligned with the sensor that detects the magnets and outputs a weight reading. These magnets are just glued onto the rod that holds the filter and these magnets need to be precisely placed on the rod too which means this can't be fixed but instead replaced.
+One possible cause was the fact that the magnets weren't in line in the mass transducer which help in recording the weights of the filters to derive a mass concentration. But this was on the PM-2.5 side which never really had any indicated problem. Later on though it was noticed that the PM-2.5 was giving very inaccurate readings compared to what it should have been reading based on readings of another air quality sampler in Grand Forks.
+The other possible and most likely cause is that the bottom power board in the TEOM computer housing cabinet was completely corroded and is most likely not supplying power properly throughout the instrument thus causing the PM-10 to not read in.
 ===Solution===
-The way that Thermo Scientific recommended to fix this issue was by replacing the whole mass transducer and replacing the head control board on the TEOM too. The reason these both need to be replaced is because they are calibrated together.
+To fix the issue with the PM-2.5 not giving accurate readings the mass transducer and head control board would all need to be replaced according to Thermo Scientific. These need to be replaced in tandem due to them being calibrated together.
+To fix the issue with the PM-10 not being read in the most plausible solution would be to completely replace the bottom power board in the TEOM.