A laptop and printer are shipped with our system....they are on the BOM. They are therefore a part of the ME. There are also many other custom components which produce emissions in the system
Let's leave safety and applied disturbances out of the discussion.
The laptops/printers are certified for US/CAN/EU to class B home use. The system must be US/CAN/EU class A, but, again there are other noisy emitters in the system besides the laptop and printer.
Question: If we change the BOM to use a different laptop or printer, do we need to repeat RF and conducted emissions
Our lab does not want to answer the question in a straightforward manner. They never say no. They have offered to rerun the tests and give us the test results but not a complete report.
There are many opinions within the engineering department
Opinion 1- Retesting is not necessary because you are substituting class B with another class B device-no need to worry that devices have different emission spectra
Opinion 2- You must re-test because the part numbers on the test report will not match the part numbers on the BOM
Opinion 3- Write a justification to eliminate re-testing...this is just as good as objective evidence
The justification would be a formal analysis that treats the new printer or laptop as point sources/currents sources with maximum class B emissions at all frequencies. It goes the math to add the additional energy to the existing test result in the form of addition dBuV/m. Finally, it is shown that the results are below class A limits.
Any thoughts?
Let's leave safety and applied disturbances out of the discussion.
The laptops/printers are certified for US/CAN/EU to class B home use. The system must be US/CAN/EU class A, but, again there are other noisy emitters in the system besides the laptop and printer.
Question: If we change the BOM to use a different laptop or printer, do we need to repeat RF and conducted emissions
Our lab does not want to answer the question in a straightforward manner. They never say no. They have offered to rerun the tests and give us the test results but not a complete report.
There are many opinions within the engineering department
Opinion 1- Retesting is not necessary because you are substituting class B with another class B device-no need to worry that devices have different emission spectra
Opinion 2- You must re-test because the part numbers on the test report will not match the part numbers on the BOM
Opinion 3- Write a justification to eliminate re-testing...this is just as good as objective evidence
The justification would be a formal analysis that treats the new printer or laptop as point sources/currents sources with maximum class B emissions at all frequencies. It goes the math to add the additional energy to the existing test result in the form of addition dBuV/m. Finally, it is shown that the results are below class A limits.
Any thoughts?