Xref: utzoo misc.consumers.house:15884 sci.electronics:16890
Path: utzoo!telly!eci386!ecicrl!clewis
From: clewis@ecicrl.UUCP (Chris Lewis)
Newsgroups: misc.consumers.house,sci.electronics
Subject: Re: Improper ground in house wiring?
Keywords: ground wire
Message-ID: <1072@ecicrl.UUCP>
Date: 11 Jan 91 07:33:23 GMT
References: <3667@ntmtv.UUCP>
Reply-To: clewis@ecicrl.UUCP (Chris Lewis)
Followup-To: misc.consumers.house
Organization: Elegant Communications Inc., Ottawa, Canada
Lines: 47

In article <3667@ntmtv.UUCP> adrian@ntmtv.UUCP (Adrian Brandt) writes:
>The unit has two LEDs on the top of it.  According to the
>very brief description on the package, the red LED indicates
>that surge protection is working and the green LED indicates
>that the unit is properly grounded.

>So, I go to plug it in and expect to see the green LED come
>on and stay on, and the red one to flicker on once in a long
>while to indicate surge supression.  Instead, as I plugged
>it in, the red LED came on immediately and the green one
>doesn't.  It stays this way whether I've got anything plugged
>into the unit or not.

I have the same unit.  Both LEDs come on.  I think that the red
one comes on to indicate that the surge supressor circuitry
is intact and not fried, whereas the green one means you have a valid
ground.  The brief instructions say that once the red one goes out,
the surge suppressor is shot.  From Radio Shack?

>Now, either the red and green LEDs are reversed (not likely),
>or the wiring in the apartment doesn't have the ground hooked
>up properly (likely).

I think that's the real problem.

>Does this mean I'm not going to get
>surge protection?  RFI/EMI filtering?  What's a good test
>to see what's going on with my power?  How do I test whether
>ground is hooked up properly?  I've got a fairly good digital
>multimeter...

It's a little tricky to test a ground with a multimeter.  There
are little 3-LED devices costing around $5 that do a good job of
testing the whole thing out.  A simple test would be to use the
multi-meter (on 200V scale) between each of the spades and the
ground socket.  One should be 110-150V, and the other should be
zero or within a few volts.  But this isn't definitive.

It may be worth while removing the cover and seeing if anything
is attached to the ground lug - especially if there's a bare wire
in the cable and it's attached to the outlet, box or there's
conduit.
-- 
Chris Lewis, Phone: (613) 832-0541
UUCP: uunet!utai!lsuc!ecicrl!clewis
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