Neutral cluster and Air Ion Spectrometer (NAIS)

Effettuata pulizia.

Servono panni ottici per la prossima volta

Issue Summary

Still unknown the reason why the overheating occurred.
After replacing all O-rings, the instrument was reactivated. However, an issue with the negative charger current was observed; instead of being at -15, it remained at 0. This issue was likely related to a problem with isolation. Such an issue could occur if the charger needle is bent and touching the cylinder, but in this case, it is more likely occurring somewhere in the isolator part.

Actions taken

1. Ultrasonic Cleaning: Performed ultrasonic cleaning on the honeycomb and the cylinder surrounding the needle.
2. Deep Cleaning: Conducted a thorough cleaning of the preconditioning unit.
3. Preconditioning Part Sent for Repair: Sent the preconditioning part of the negative column back to Airel for repairs 05/07/2024.
4. Adjustments Made: The part was repaired and returned. Post-repair, the current fluctuated, and there was a constant warning of "negative charger current fluctuating," but it is deemed negligible.

Follow-Up and Testing

• The instrument was run in Bologna for a week before being reinstalled here on July 31.
• A cleaning of the columns was performed.
• Leakage Check: When the inlet is plugged, if I put my hand on the inlet the flow values are 0 in the negative column and 7 in the positive column, which should not pose a problem.
• Additional Needs: More optical cloths are required for the next maintenance session.

Current Status

The instrument is operational with a minor, negligible warning regarding the negative charger current fluctuation. There are no expected internal leaks, and the system should function as intended.

Recommendations

• Monitor the negative charger current to ensure fluctuations remain negligible.
• Ensure the availability of additional optical cloths for future maintenance.

Very noisy since the dust event happened a cleaning was needed.

After removing the case we found black material coming from the connection of all the electrometers(both neg, pos column and 2 discharger sockets) and some wierd black spots aroud the uppercase and copper inlet tube.

Transfer to Bologna lab for better checking.

The columns have been cleaned. (Panni ottici rimasti per la pulizia: 5 spessi, 5/6 fini)

Sample flow was very low during the previous week due to ice formation on the entire inlet wall, obstructing the sampling of air.

The heating system has been reactivated.

Pulizia delle colonne