| WARNING When maintaining the forward scatter sensor, do not look at the transmitter of the forward scatter sensor from the beam direction. |
- 1
- Transmitter window
- 2
- Main receiver window
- 3
- Side receiver window
The sensor can compensate for a reasonable amount of window contamination, but when a certain limit is exceeded, cleaning is required.
Vaisala recommends cleaning the transmitter and receiver windows:
- Annually. If the conditions require, clean more often. For example, at airports, clean every 3 months.
- When the response to a status command includes a contamination warning (W) or alarm (A).
- When suggested by the guided window check (mode windowcheck).
| Without maintenance connection | With maintenance connection | ||
|---|---|---|---|
| + | Laptop not needed | − | Laptop needed for establishing maintenance connection |
| − | No immediate indication of success | + | Indicates cleaning success |
| − | No metadata of cleaning date | + | Stores the cleaning date as metadata |
| − | No indication of adjustment needs | + | Indicates need for adjustment |
| − | Measurement values are disturbed by cleaning process | + | Measurement values are slashed/invalidated during cleaning process |
While cleaning the windows, also clean Vaisala HUMICAP Humidity and Temperature Probe HMP155 and the window of Vaisala Background Luminance Sensor LM21 if installed. For instructions, see HMP155 User Guide (M210912EN) and Background Luminance Sensor LM21 User's Guide.