MDT Chamber Temperature Overview

This panel provides a map of the temperature distribution in the muon spectrometer region of the cavern, based on the MDT chambers' temperature sensors.

MDT Temperature Sensors.

There are 3 types of temperature sensors on the MDT chambers; the first two are read out by the MDM box (Muon DCS module) of each chamber and differ only in type (PT100 type sensors for the EM and EO chambers, NTC type sensors for the barrel chambers). The third category are the sensors read via the endcap alignment system. Different DCS projects handle the sensor data acquisition.

Color Map. Color Scheme.

The color map provides a graphical representation of the temperature distribution in the ATLAS cavern. For each MDT chamber, the value shown corresponds to the average of the chambers' sensors, with for robustness the smallest and largest value excluded from the calculation of the mean if the chamber has at least 4 temperature sensors. The following colors have specific meaning:

• White: Chamber is not equipped with T-sensors. This is the case in particular for the BEE chambers.
• Dark Grey: Temperature data of a chamber is invalid; see trouble shooting section below.
• Dark Blue: Under Flow, temperature average of a chamber is smaller than the set lower limit of the value range translated into colors.
• Dark Red: Over Flow, temperature average of a chamber is larger than the set upper limit of the value range translated into colors.

Normal temperatures are from about 18 degrees, at the bottom of the cavern, to about 25 degrees in the top sectors.

Interactive Control. Buttons and ToolTips.

The following holds only if the panel is opened from the DCS user interface, not for the Web Status Pages which are non-interactive! Consequently the buttons at the top of the panel are only visible if the panel is opened from the DCS.

• ToolTip: Placing the mouse pointer over a chamber will display after some seconds the current temperature value and the chamber name.
• Limits: Pressing this button opens a drop down menu where the lower and upper limit of the color bar can be changed/set. This allows a zoom into the temperature value range. Selecting the option 'Automatic limits' activates the automatic calculation fo minimum and maximum temperatures from the data.
• Trend Plots: Pressing this button brings you to the panel providing access to the temperature history for selected chambers.
• Auto Update: If checked, the color map is refreshed every few minutes with the current temperature data. If not, the display updated only when pressing the 'Refresh' button.
• Refresh: Recalculate color map based on latest temperature values.

Trouble Shooting.

Here are some hints what to do if you think the panel is not working as it should:

• Individual chambers show 'Invalid Data': If only a few individual chambers are marked as having invalid data (chamber shown as dark grey), ignore it, there may some MDM nodes disconnected etc. This holds in particular for the shutdown period outside LHC running.
• All Small Wheel (EIS1,2, EIL1,2) and All EMS1 chambers show 'Invalid Data': This situation is normal when the endcap alignment system is NOT running, as is usually the case outside data taking periods. No actions needed.
• A large number of chambers other than the Small Wheel/EMS1 show 'Invalid Data': This inidcates that the temperature data acquisition has been stopped. If the situation stays, you can contact atlas-mdt-dcs@cernNOSPAMPLEASE.ch.
• The time stamp in the left-middle of the panel indicates data is outdated: This indicates the color plot has not been updated recently. If the panel is run from DCS, check that Auto-Update is checked. If the panel is viewed as a Web Status panel, contact atlas-mdt-dcs@cernNOSPAMPLEASE.ch.

Questions and Comments.

This panel is maintained by MDT DCS. Contact us if needed.

-- StephanieZimmermann - 27 Jan 2009