We're being hit with a requirement that I don't understand. 

We are using a shielded Ethernet connector that contains the typical 2kV
cap from the common point of the 75 ohm resistors to the shield.  This
is used on the output of an off-the-shelf Ethernet transceiver module,
and the mfr of that module is telling us we need to connect the
connector shield to their digital ground through a 1nF 250V Y-cap, not
directly.  

1. Why not directly connect the shield to digital ground?

2. Why would a Y-cap be required?  The cap would be joining two parts of
the same circuit, so it would not be across an isolation boundary.  I
can't think of a reason to require either the 250V rating or the Y
rating.  

Any thoughts anyone?

Thanks,

Jim Eichner, P.Eng.
Manager - Compliance Engineering
Xantrex Technology Inc.
e-mail: jim.eich...@xantrex.com
web: www.xantrex.com

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