I've heard it mentioned that one way to reduce the effects of EMI on these machines, is to separate the VFD from all the other components and mount it in its own metal enclosure.
This has its drawbacks in regards to hardware required and a neat build.
I was wondering if the same or similar results could the gained by just installing a steel mesh enclosure over the VFD, in its existing location? The mesh would still allow effective cooling, but will it counter act EMI?
I think the best way to reduce EMI is going to be proper cable shielding and proper grounding. The enclosures main purpose is normally to protect and consolidate electronics. Cabinets do provide limited shielding and additional wall shielding lining can help some more. A good cooling/fan system on an enclosure can actually help a VFD run cooler due to the increased air flow around it. Any "mesh" enclosure would have to be similar to cable mesh and would be not only costly vs benefits, it would hinder cooling and installing a proper cooling/fan system to manage airflow would be difficult.
All industrial machines I have seen had VFDs in the same enclosure with the PLC and the rest of the electronics. No special EMI protection other than AC input filters and shielded cables between VFD and motor.
Ok, it sounds like there is not much benefit in regards to EMI shielding with fitting mesh around the VFD.
I am going to improve the shielding , in regards to cabling anyway, as well as earthing.
I'll probably put the VFD in its own box anyway to make some room for my new ESS and MB2 in the main enclosure.
If the mesh was an option, I was considering just moving everything into a new larger casing, as its pretty snug in there now.
Steve
Steel mesh enclosure to reduce EMI
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