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Posted By: stan telephone - 08/21/01 11:26 PM
how close can a telephone be to a bath tub enclosure ? maybe 3 feet?
Posted By: Bill Addiss Re: telephone - 08/22/01 12:27 AM
Stan,

Your best bet would be to think cordless. Chances are that no matter where you put it in the room someone could still use it in the tub.

Bill
Posted By: sparky Re: telephone - 08/22/01 12:29 AM
hmmmm,
well Stan, i really do not know, and cannot find any NEC either. It does bring to mind phones outside, phones by the pool, portable vs. cord connected phones, cell phones in a hot tub....

Does any forum memeber know of a phone related incident here???
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(other than using it as a projectile...)
Posted By: Bill Addiss Re: telephone - 08/22/01 01:46 AM
Sparky,

I think I've heard of lightning related instances where someone was killed while talking on the phone.

Bill
Posted By: sparky Re: telephone - 08/22/01 01:56 AM
ouch!
and to think they were probably billed for the call!
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Posted By: Anonymous Re: telephone - 08/22/01 02:22 AM
Sounds like an ungrounded telephone if the lightning came in on the telephone.
Posted By: Bill Addiss Re: telephone - 08/22/01 04:38 AM
This is all I was able to find so far:
http://www.urbanlegends.com/death/phone_electrocution.html

Bill
Posted By: pauluk Re: telephone - 08/22/01 10:22 AM
Hi Stan,

Our "code" in Britain allows no electrical light switches or other accessories to be within reach of anyone in a bathtub or shower, the min. distance to meet this requirement being specified as 6 ft.

Bearing in mind the telephone line carries 50V DC when idle and up to 100V AC when ringing, I would exercise the same degree of caution.

Another point to consider is that most domestic telephone equipment is not really built for moist atmospheres, and you could have problems with steam condensing inside the unit.

Back when our telephone network was state-owned and the P.O. installed all the wiring (pre 1982) requests for any telephone apparatus in a bathroom were refused point-blank.
Posted By: sparky Re: telephone - 08/22/01 11:18 AM
I did hear a concern once about cell phones and pagers being inadvertintly brought into hazardous locations.

My impression is that one could pursue rating /listing requirements here to install said phone in the shower, right next to the NEMA rated panel as we seem to entertain such folly.

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Posted By: Anonymous Re: telephone - 08/22/01 07:57 PM
I have seen lightning damage done when the telephone was not bonded to the electrical GES.

I have no doubt that a person would have been harmed in some of these instances had they been in the wrong place.
Posted By: pauluk Re: telephone - 08/22/01 09:50 PM
Quote
Originally posted by Dspark:
I have seen lightning damage done when the telephone was not bonded to the electrical GES.

Is it currently standard practice for lightning arresters to be fitted on tel. lines where they enter premises?

This isn't done here, but then we don't get anything like the number or severity of storms that many parts of the U.S. get.
Posted By: sparky Re: telephone - 08/22/01 10:13 PM
I see a lot of older telephone entrance that has a lightning arrester, usually it is two 3 or 4" cylinders about 1/2" in dia.
I don't see this on newer installations.
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Posted By: Anonymous Re: telephone - 08/22/01 10:19 PM
The old ones had the gas discharge tubes you described. The new ones have something different. But they still must be bonded to the AC system's GEC.
Posted By: pauluk Re: telephone - 08/23/01 05:43 PM
Quote
Originally posted by Dspark:
The old ones had the gas discharge tubes you described. The new ones have something different. But they still must be bonded to the AC system's GEC.

Do they perhaps use MOVs (Metal Oxide Varistor) as the modern equivalent? These seem to be the current method for surge protection in power strips and tel. line protectors for computer equipment.
Posted By: Anonymous Re: telephone - 08/23/01 09:00 PM
> Do they perhaps use MOVs
I haven't opened up the telco side to check. I'll have to look.

My guess would be a cheap choke that shunts the magnetic field to ground.

MOVs would have to be checked after every event and replaced if damaged. MOVs are relatively expensive compared to iron chokes.
Posted By: sparky Re: telephone - 08/23/01 09:18 PM
I have seen nothing to insinuate this protection on the premisis, perhaps it would be on the pole??
Posted By: Anonymous Re: telephone - 08/23/01 10:17 PM
>I have seen nothing to insinuate this protection on the premises
Seriously? All telephone network interface boxes have a solid copper wire attach to the GES or similar and tagged with a statement to the effect that the wire must not be disconnected or else the house will burn down and if you see one disconnected, call the telco.
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