Humidity Sensor. Broken?

We have a small server room with 8 42U racks. There are 3 air con unit in this room.

We are using a humidity sensor with uses PoE. Im not sure on the model but it looks like this:



http://upload.wikimedia.org/wikipedia/en/f/f2/Serverscheck_sensor.jpg



The problem that we are having is everyday at around 23:00, 08:00 and 16:00 the humidity sensor sends an email alert which is shortly followed by an OK email.



The first email looks like:

status of Room Humidity ( - ) changed to DOWN at Tue Jul 10 07:42:25 2012. Reason: Error: Error level: 66.2 (returned value) greater than 65



And the second:

status of Room Humidity ( - ) changed to OK at Tue Jul 10 07:43:11 2012. Reason: Recovered from last error: Error level: 66.2 (returned value) greater than 65



This has been happening for a few weeks everyday. I have checked the sensor and their doesn't appear to be anything wrong with its physical location.



What step could be taken to resolve this?

The sensors don't look broken at all. I think it is an issue on your server room in respect to humidity levels. If it is always at the same time then it looks like the room gets dehumidified around the same time every day.

Ok, The sensor is on top of one of the server racks. Would the location of the sensor be causing the issue?

What steps could be taken to solve the rapid humidity changes?

We aren't talking about rapid humidity changes but a 1% change



The errors are around 66% where your threshold is 65%

There is a rapid change in humidity at points throughout the day. The normal humidity is around 50% but jumps to 66-68%.



The image shows the last 7 days.

You could use another unit to verify humidity levels in the room. Another way of doing it is to move it to a room that is not cooled by an AC unit