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Errors

“Fatal Error 1420” is related to the door or heated cover not being fully closed on the instrument itself. We recommend opening the front access door using a small screwdriver, ensuring that all inner components are correctly seated, then closing the door completely. Please then reboot the instrument and attempt to restart your run. Please see page 60 of the Installation and Maintenance Manual for more information. 

You may get a message that the heated cover is not reaching the set temperature. If you get this error, or notice this issue on your own, please contact us at instrumentservices@thermofisher.com.

Sometime there is an error such that the ROI will not calibrate all 96 wells. If you run into this problem check the following:

  • Is the ROI calibration plate old or expired?
  • Spin down the plate and visually inspect the wells. Is the volume consistent and correct across all wells? If not, try a new ROI calibration plate.
  • Try the manual calibration and increase the exposure time.
  • Check the status of the halogen lamp. If it is over 2,000 hours, replace the bulb and try again.

 

If you have tried all the steps above but the ROI still will not calibrate, please contact us at instrumentservices@thermofisher.com for further assistance.

If you see this error message, please check the following:

  1. Verify that the USB connection is secure between the instrument and computer.
  2. Verify that the computer user power save settings are set to Never for all users (in Windows under Control Panel, Power Options).
  3. Is there a screen saver in use? If so, set the screen saver so that it will not come on during a run.
  4. Is there antivirus or other network software in use? If so, disconnect from the network while running the instrument.

If the error persists, please contact us at instrumentservices@thermofisher.com for further assistance.

This error can be caused by the wrong plastics being used in the block, such as the wrong Precision Plate Holder being used in the tray. This can give an error message such as “Block up switch not activating” and will not allow the run to start. Open the drawer, make sure the correct plate/tubes and plate/tube holder are being used and in the correct orientation. Turn off the instrument and open the front cover to make sure the heated cover door is closed. Restart the instrument and retry the run. If the error still persists, please contact us at instrumentservices@thermofisher.com for further assistance.

You may encounter this error message, which will abort the run before it even starts. If so, go into the software under Setup → Run Method and check how much time has been set for the data collection step. The instrument has a minimum collection time, which is dependent on the number of filters being used. (This is true in both the 1.x and 2.0.x versions of the 7500 software.) Increase the extension time to 30 sec and restart the run. It should now proceed as normal. The example below is shown using the v2.0.x software, but the same general steps should be taken in v1.4 as well to correct this error. If the error persists, please contact us at techsupport@lifetech.com for further assistance.


If you have the SDS v1.4 or earlier, you will need to open the dd CT plate in a Study first in order to see the CT or RQ values. (If you have v2.0.x this error does not apply.)

  1. After the initial run is complete, open, review the plots and save it. Then:
    • Choose File → New
    • Choose: Assay → ddCT (Relative Quantitation) Study. Set the other parameters as appropriate and click Next.

  2. Click on ‘Add Plates…’, then browse to where your data file is located and select the plate (or multiple plates).
    Click ‘Finish’, and you should see your study.

The 7500 software requires that the endogenous control be run on every plate within a study. If not, you will only see RQ values for the plate that contains the endogenous control on it. The other plates will have CT values for all the wells, but the software will not calculate RQ values. If you designed your experiments in this type of layout, you will want to do your analysis in the free DataAssist™ software instead. This program does not have the endogenous control requirement for every plate. Simply export the study results file from the 7500 software as a *.txt or *.csv file, and use that to create a new study in the DataAssist™ software. You should now be able to see RQ values for all samples, even those without an endogenous control on the same plate.