Vanagon EuroVan
Previous messageNext messagePrevious in topicNext in topicPrevious by same authorNext by same authorPrevious page (July 2012, week 2)Back to main VANAGON pageJoin or leave VANAGON (or change settings)ReplyPost a new messageSearchProportional fontNon-proportional font
Date:         Wed, 11 Jul 2012 13:49:39 -0400
Reply-To:     David Beierl <dbeierl@ATTGLOBAL.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         David Beierl <dbeierl@ATTGLOBAL.NET>
Subject:      Re: re-doing unsafe 120 volt wiring, add GFCI?
Comments: To: Loren Busch <starwagen@GMAIL.COM>
In-Reply-To:  <CAH32RNZ_kGEjuBkAHMzs19+zLDCbMBTmCTik-KY4K6b_X3OckQ@mail.g
              mail.com>
Content-Type: text/plain; charset="us-ascii"; format=flowed

At 12:33 PM 7/11/2012, Loren Busch wrote: >While on this subject let me add an additional safety suggestion. Get a >line tester and/or a 120v plug in meter. Both are avialable from places >like Camping World. And use them to test the shore power you are plugging

By line tester I imagine you mean the three-prong plug containing three neon lights, which will tell you whether hot and neutral are reversed, and neutral or ground open.

It's an useful tool, and I heartily endorse carrying and using one. However it's got an important limitation for testing power connections, which is that it places only a tiny load on the circuit, so it won't give you any warning of a poor connection.

A solenoid meter (electricians call them "Wiggys" for historical reasons) like this one http://www.grainger.com/Grainger/wwg/search.shtml?searchQuery=wiggy&op=search&Ntt=wiggy&N=0&GlobalSearch=true&sst=subset will put a bit more load on because it indicates voltage by actually pulling a solenoid core down against a spring, like a lightweight spring scale. It's more nuisance to use and costs more, and you have to understand or write down a table like the one printed on the little plug-in guy, but does give some indication whether the ground or neutral connections can actually carry some current -- if it shows a different reading hot-neutral vs hot-gnd, for example, you know there's a problem in the one with the lower reading.

If you look at a standard three-prong socket, think of it as a little man's face, with the U-ground opening his mouth and the two slits his eyes. His left eye (on your right as you look) will be shorter, and that's HOT. His right eye is NEUTRAL and his mouth is PROTECTIVE GROUND.

A correctly wired socket will show H-N 120 V; H-G 120 V; N-G 0 V.

Hot-neutral reverse (the common problem) will show H-N 120 V; H-G 0 V; N-G 120 V. I would not recommend to connect to this, as devices like table lamps which are wired to keep the hot terminal protected will now have it exposed, or more exposed.

Open ground will show H-N 120 V; H-G 0 V; N-G 0 V. I would strongly recommend not to connect to this, as any faults or leakages in devices including van wiring will cause the van chassis to become hot with respect to earth.

Open neutral will show H-N 0 V; H-G 120-240 V; N-G 0 V. In a house or campground wired US-fashion this is a dangerous situation which can start fires in small. DO NOT CONNECT to this. I'll explain why separately.

Ground-neutral reverse will meter as normal. This is not a good situation but unless I'm forgetting something I don't see how you can tell from the socket.

There's another instrument that saves electricians' and telephone linemen's lives - a non-contact voltage detector like this: http://www.grainger.com/Grainger/FLUKE-Voltage-Detector-2KU25?cm_sp=IO-_-IDP-_-BTM_BTB05209020&cm_vc=IDPBBZ2 Hold it next to something that's got 50 VAC or more sitting on it and it will complain.

Versions of both of these will be available at your local electricians supply house and probably at H-D/Lowes etc as well. Both good investments for dealing with AC supply circuits.

And to the original question, I think a GFCI is a good idea.

Does the Westy really have a 6-ga bonding wire? I'm surprised they'd use one so large (but I know zip about Codes...).

Yours, David


Back to: Top of message | Previous page | Main VANAGON page

Please note - During the past 17 years of operation, several gigabytes of Vanagon mail messages have been archived. Searching the entire collection will take up to five minutes to complete. Please be patient!


Return to the archives @ gerry.vanagon.com


The vanagon mailing list archives are copyright (c) 1994-2011, and may not be reproduced without the express written permission of the list administrators. Posting messages to this mailing list grants a license to the mailing list administrators to reproduce the message in a compilation, either printed or electronic. All compilations will be not-for-profit, with any excess proceeds going to the Vanagon mailing list.

Any profits from list compilations go exclusively towards the management and operation of the Vanagon mailing list and vanagon mailing list web site.