Upon startup the IOC communicates correctly with each dust monitor until it gets to location 16 (the one that was swapped yesterday). After this it starts reporting back errors of the form:

Error: ../commands.c: 49: Sent command � not echoed
Received ?

I powercycled the Comtrol this morning. It worked after location 16 for a little while, but the error has returned.

Robert says he swapped the dust monitor in the H1 PSL laser enclosure.

First one dust monitor was disconnected from the breakout box outside the entire H1 PSL enclosure. If I recall correctly, the dust monitor at location 16 was then still found by the IOC. The communication errors persisted. The first dust monitor was plugged back in and the other one disconnected. The IOC still found the dust monitor at location 16, but the communication errors went away. The dust monitor at location 16 reported calibration errors.

It may be that the wrong dust monitor was swapped, leading to two set at the same location number, but this would not explain why the communication errors persisted after the first one was disconnected.

As it stands, one of the dust monitors in the H1 PSL enclosure is disconnected. The dust monitor at location 16 is reporting calibration errors. I am not sure where the dust monitor at location 16 is. The dust monitor at location 10 is not found by the IOC. The remainder of the dust monitors in the LVEA are running again.

Sheila swapped the dust monitor in the anteroom with one programmed at location 10. The one she removed from the anteroom is labeled 'H'. It had no charge left in the battery when I got it.

There was no change in the status. The dust monitor at location 10 is still unseen, and the dust monitor at location 16 is still giving calibration errors.

This leads me to believe that:
The dust monitor at location 16 is in the laser room and has calibration errors.
The dust monitor at location 10 is in the anteroom and is unplugged at the breakout box outside the enclosure.