Do you have an error 6 message displaying on your Hettich Universal 320 or 320R centrifuge ?
Error 6 may be caused by an error in lid locking or lid closure.
The first thing to try is a mains reset. To perform a mains reset the operator should switch off the mains switch located at the back of the centrifuge for the universal 320 (non refrigerated model) or right hand side for the universal 320R (refrigerated model). Then wait for at least 10 seconds before turning the mains switch back to the on position.
If the error 6 message displays again then it is likely that the lid lock mechanism needs replacing.
This is available to buy direct from Hettich in Germany or any of their dealers which will vary depending where in the world you are located.
Here is a link to the operators manual on the manufacturers website.