#Emc compliance engineer how to#

My product is in a stainless steel enclosure with a diagonal 4.3' (approx 110 mm) rectangular cut out for an LCD display, two 22mm hole cut outs for buttons Particularly in case of RF products as is the case here. Though my general experience of EMC testing is to not stare blindly at which specific frequencies you were having problems, since it's fairly complex to translate those (and harmonics) to something corresponding to your product.Īlso if you have problems with susceptibility you might have problems with emissions too. Or just provide more details about the supply electronics in a separate question and some power guru could do a design review (layouts have to be done very carefully). In case of switching buck regulators, investigate if the frequency might have something in common with the problematic frequencies. PCB layout, power electronics layout and grounding would all be the usual culprits to investigate. So if you fail the EMC test even with such lax requirements, I would suspect that you have some severe problems in your product beyond shielding/encapsulation.

So your pre-compliance test is using relatively very low requirements with 10V/m susceptibility and in a reasonably small frequency range. Sounds good to me, though your test house should know these things. How about:ĮTSI EN 303 454 'Short Range Devices (SRD) Metal and object detection sensors in the frequency range 1 kHz to 148,5 kHz '. You should probably be using some EN/ETSI ones to test the intentional radiation as well as the unintentional. I also find it weird that general EMC standards are used on what's clearly a RF product. Any help or suggestions would be great and I can supply further information if needed.įirst of all, note that some industrial applications might actually require 100V/m susceptibility (such as land-moving machinery, stone crushers, drilling rigs etc). Knowing that the device fails at these two particular frequencies, and knowing that adding a shielded mains power cable greatly improved the pass rate, what information do I have here in order to investigate further? I feel like adding more shielding is a band-aid approach and would like to remove the shielded mains cable completely if I can determine and fix the root cause. This reduced the number of failures to just specifically those two frequencies (rather than the whole range between).

I then changed the 1.8m mains power cable to a same length shielded cable and also connected this shielded cable to the enclosure. Initially during this test, the device failed at all frequencies betwen 470MHz to 520MHz. Coming out from the bottom of the enclosure is 2x 5m coax cables to connect a transmit and receive coil and 1.8m mains power cable. My product is in a stainless steel enclosure with a diagonal 4.3' (approx 110 mm) rectangular cut out for an LCD display, two 22mm hole cut outs for buttons. Specifically the test that my product failed was on:

#Emc compliance engineer how to#

I've never developed a product before (previously I've only contributed to prototype designs) so I'm not 100% clear on how to fault find in case of EMC failure.

I'm currently designing a new metal detector product and took it for pre-compliance as I've finished the hardware design and am currently finishing up on the software.