Ferrite Cores

Recently, we lost two ports (13 and 14) on our V5 brain, due to what I believe is static. After some research, I found someone suggesting to use a Ferrite Core on each end of long cables. They said that they were ruled legal in last year’s Q&A, but I cannot find it.

Is anyone able to confirm or deny this? Perhaps you have better strategies to protect the brain? (Can’t make the cable shorter).

I believe this is the Q&A you are referencing:
https://www.robotevents.com/VRC/2018-2019/QA/188

However, it is important to note that previous season’s Q&As do not carry over to the new game. You must ask in this year’s Q&A for a new ruling (though you should include a link to last year’s Q&A entry).

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Nice find. I’ll definitely ask about it with the link you provided. Thank you!

A ferrite core would not qualify as a wire management device as described in the QA. Its function has nothing to do with wire management. The product in the QA was for wire management that also happened to be shielded.

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Not sure a ferrite core on a cable or a shield sleeve will protect against ports being fried by ESD (electrostatic discharge). They mostly protect against EMI (electromagnetic interference) which can mess with your signals. Ferrite catches EMI and dissipates it as heat. ESD causes EMI so you get protection that way, but I don’t think it will prevent your brain ports from going dead. Staticide sprayed on field, not dragging your unconnected ends of cables while plugged into brain, not mounting the brain via the built-in screw holes but via the plastic bracket accessory thing instead, touching some grounded metal before you touch your robot, etc., those are the few tricks that have been suggested. I’m not an expert - @jpearman should be kindly summoned for this one - but that’s my understanding. Please correct if wrong. Our teams are constantly losing ports as well. With 8 motor limit and not much in terms of v5 sensors it is manageable and we don’t feel like complaining, but still, these things are not cheap. Winter is coming to our neck of woods, heat is on, air is dry, there is carpet everywhere, ESD is a real thing so we’d like to hear some good intelligence on this as well.

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Yes. About 1 hour after spraying down the field, we got a WSOD and a blown port. @Zenix can attest. The brain was replaced for unrelated reasons.

Question for VEX staff about that

Any idea why we got 2 brand new brains back in place of the one we got replaced?