EMI/EMC weighing M/c Tested for Susceptibility failed

[kumar]

Hi!

I got a electronics weighing M/c Tested for Susceptibility test. It failed between 350 - 450 MHz. The test range was 80 to 1000 MHz. Could someone help me with the reasons for this happening.

Thanks

Bye!

 

[crono]

Hi.

There are many reason for failing in EMC tests.

Can be more specific, please? What appen to your unit?


Some points to :
- What about your analog inputs? If you are using OP-Amp are the inputs correctly filtered?

- What about your PCB? Are you using a correctly routed PCB? (From EMC point of view). Is your ground path right?

- What about your casing? (Is a good shield?)

- What about cables connected to your unit? (are they filtered?)

This can be only a starting point... but anyway..

GOOD LUCK !!

 

[House_Cat]

Since you failed susceptibility is such a specific band, I would look for resonant structures.

Look for an opening in the shield/case that could be acting as a waveguide for the band you failed. Cable entryways are frequent sources.

Look for circuit areas (long traces, wires, etc) that could be resonant antenna structures - a Grid Dip Meter can be helpful in this endeavor.

Without more specific information, the above is all I can immediately think of.

 

[sundargold]

Re: EMI/EMC

check your filter circuit clearly once again.