Path: utzoo!mnetor!uunet!nbires!hao!ames!umd5!cgs
From: cgs@umd5.umd.edu (Chris Sylvain)
Newsgroups: sci.electronics
Subject: Re: How to connect grounds when using RJ11 for RS232
Message-ID: <2301@umd5.umd.edu>
Date: 16 Feb 88 02:30:01 GMT
References: <6561@tut.cis.ohio-state.edu>
Reply-To: cgs@umd5 (Chris Sylvain)
Organization: University of Maryland, College Park
Lines: 23
Keywords: ground-loop

In article <6561@tut.cis.ohio-state.edu> mdf@tut.cis.ohio-state.edu (Mark D. Freeman) writes:
<
< The cable's shield ought to be connected to something, but all the connectors
< are plastic.
<
< The question, what do I connect the cable's shield to?  If I can only
< connect one ground, which should I hook up?  If I can hook up both,
< should I bother?
<

Not knowing if all your terminals are all one the same AC circuit, nor if they
all live on the same phase of the AC service in the building, and you
definitely don't want to CREATE a ground-loop, then I suggest you connect the
shield to earth ground AT ONE END ONLY.

With the single ground connection you can at least have the electrostatic
shielding of the cable's shield, without having a connection which would
provide a path for ground currents.
-- 
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