Troubleshooting

If you experience inaccurate dispense volumes with MANTIS, there could be a problem with the instrument’s pressure and vacuum regulators or solenoids. To check the regulator and solenoid functionality, you can use the Pneumatic System Check wizard.

Prerequisites:

• You are running MANTIS 4.1 or newer.

 

To check the pneumatic system functionality:

1. Go to the Tools menu and select Pneumatic System Check.

   Important: Make sure that there is no chip attached to the MANTIS before performing the test.

2. At this point, MANTIS will check the functionality of the pressure and vacuum regulators. The check will involve testing the pressure and vacuum generated by the regulators for dispense with diaphragm chips, and the pressure / vacuum switch value used for Continuous Flow dispense in CF enabled MANTIS V3 systems.

3. After the check has completed, a table will appear which displays the range of pressure, vacuum, and P/V switch values (if applicable) generated during their test, the average value within that range, and the expected values for optimal MANTIS performance. A green check icon indicates that the generated values are within the expected range, while a red cross icon indicates that the generated values are outside of the expected range. If any of the generated values are outside of the expected range, please contact FORMULATRIX support for assistance. If there are no errors with your regulators, click Solenoid Check to continue with the Pneumatic System Check wizard to test the solenoid functionality.

   

   Pressure, Vacuum, and P/V Switch Values in the Pneumatic System Check Window

4. Now MANTIS will check for stuck solenoids. After the test is finished, the results will be displayed in the Pneumatic System Check window. A green check icon indicates that a solenoid is not stuck, while a red cross icon indicates that a solenoid may be stuck.

   

   Solenoid Check Results in the Pneumatic System Check Window

5. If MANTIS suspects one or more solenoids of being stuck, you can then confirm whether or not a solenoid is truly stuck using an audible test. Stuck solenoids do not make any sound when actuated, while functional solenoids produce an audible sound. Click Expected Sound to listen to what a solenoid valve should sound like when it opens and closes.

6. Click Check to listen to the sound of the solenoid suspected of being stuck.

7. Compare the expected sound with the good solenoid sound from your hardware.

   1. Click Yes if the sound from the tested solenoid is similar to the sound you hear when you click Expected Sound. This means that the solenoid works properly.

   2. Click No if you do not hear any sound from the hardware. If you do not hear anything, the solenoid is not working properly. Contact FORMULATRIX support for assistance if you have one or more stuck solenoid.
      

      

      Multiple Solenoids are Stuck
      

8. Close the wizard.

Incorrect dispense volumes may occur if the chip type in use is different from the chip type selected in the MANTIS software. Check that the chip type selected in the software is correct; if not, select the correct chip type. See Input Control Panel for modifying and selecting your chip types correctly.

Check the tube connection and make sure it is firmly attached to the chip/tube input. If you see either if these issues after the first dispense or after the chip returns in between reagents, then make sure you are priming the chip before each dispense. Failure to prime a chip will prevent accurate dispenses. Please also note that it takes approximately 150-200 µL to prime the chip for the first dispense.

Sometimes the chips wear out. We recommend that you try dispensing with multiple chips. If the problem persists, contact support by emailing support@formulatrix.com. If you are on maintenance, you will be shipped a loaner MANTIS, instructed to ship yours to support for repairs, and when you receive the repaired device you must ship back the loaner.

Usually this issue is caused by a misalignment of the wash position. To fix this problem, you will need to edit the sequence file. Contact support by emailing support@formulatrix.com and a support representative will walk you through the process.

If your computer is showing that MANTIS USB drive is read-only, you will not be able to use the software because the software frequently writes to the USB drive. There are two ways to fix this issue. 1) Contact support by emailing support@formulatrix.com. FORMULATRIX will send you a loaner MANTIS if you are on maintenance and replace the USB drive on your MANTIS. 2)To fix this issue, copy the contents of the USB drive onto your computer, so that when you run the software you are running it locally instead of from the USB drive. Or if you are on maintenance, you can contact support by emailing support@formulatrix.com to get a replacement drive.

These problems are caused by USB communication issues. Please contact support by emailing support@formulatrix.com. If you are on maintenance, they will issue a loaner device to use while yours is repaired.

This issue can be fixed by calibrating the chip port positions.

• Make sure that you have accurately registered your plate definition in the Plate Type Library. For more information, see Adding Plate Types to the Plate Type Library.

• If the plate definition has been accurately entered but the problem persists, you can fix the deck geometry settings. Go to the Tools menu and select Deck Geometry Correction, then follow the on-screen instructions. For more information, see Deck Geometry Correction. For assistance using the Deck Geometry Correction Wizard, contact support by emailing support@formulatrix.com.

• If you are attempting to open or close the dispense design using a spreadsheet program such as Microsoft Excel, it can take a few moments for the software to translate your actions. Please be patient.

• Check that you are not in Summary View or Volume Error View. These two views will "freeze" the rest of the interface. Switch back to Designer View in order to enable the rest of the software's functionality. To change views, click the button at the top of the plate designer to display the alternative views.

 

The MANTIS Software Seems Frozen

In the case liquid being spilled on top of the chip, the liquid can enter the MANTIS Air Ribbon when the chip is being picked up or dropped off. Liquid can also enter the Air Ribbon if a chip fails catastrophically (diaphragm or valve rupture). If you ever notice liquid droplets in the Air Ribbon, you must purge the liquid to prevent it from entering the solenoid bank and damaging the MANTIS hardware. Follow these instructions to purge liquid from the Air Ribbon.

Air Ribbon at the Back of the MANTIS Arms

To purge liquid from the Air Ribbon:

1. In the Tools menu, select Purging Tool.

2. Click Start to begin the purging process.

   

   Starting the Purging Process

3. The default time for the purging process is five minutes. If the liquid is completely gone from the Air Ribbon in less than five minutes, click Stop to end the process.

   

   Stopping the Purging Process

4. Optional: Repeat steps 1 and 2 if there is still liquid in the Air Ribbon, until it has all been purged.

5. Click the Cancel or Close button when you are finished, or to abort the process and close the Purging Tool wizard.