telephone wire polarity

Maybe phones auto-correct for polarity. It doesn't matter for ringing, since this is 100V DC, but I would expect that tip & ring must be connected properly - at least from what I remember from my basic telephone electronics seminar back in '81 :-)

Reply to
Pat Coghlan
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No, it's no big deal if everything is working OK. Any problems it would cause woud show up right away so you should be OK.

They "should" be changed if you feel up to the challenge someday but no rush. The right cheap answering machine, some modems, and especially old telephones might care, but ... Symptoms of the reversal could range from not being able to draw dialtone to intermittant operation, or another phone might "ding" during dialing if you were to use a rotary phone, that sort of thing.

The polarity seldom matters anymore, though.

HTH,

PopS

Reply to
Pop

Reply to
Pat Coghlan

Yes, phones do auto-correct for polarity; most of them anyway.

Also, ring voltage is 100 V ac at normally 30 Hz, not DC, is current limited, and it is superimposed on the nominal 48V DC battery voltage. If the ring voltage detector doesn't have a bridge ckt to account for either polarity, then ringing voltage can easily not be detected. Most decent products have a brdge ckt for the purpose. 45Vac is the usual design spec to detect ring voltage rise.

Also, you shouldn't post to newsgroups in HTML mode - many people may not be able to read or make out your response from all the tags that can appear; many others won't bother to read it. You should use Plain Text mode only for newgroups. ....

HTH,

PopS

Maybe phones auto-correct for polarity. It doesn't matter for ringing, since this is 100V DC, but I would expect that tip & ring must be connected properly - at least from what I remember from my basic telephone electronics seminar back in '81 :-)

Reply to
Pop

The only phones that care are the original bell system touch tones. They won't dial.

Reply to
gfretwell

While going by "wire colors" is not 100% advisable. As different wires may have different colors.

If you have some sort of meter.

Try reversing the red and green.

Or the black and yellow.

And see if the "meter" tells you it's okay.

These are very vague suggestions, but all we can do is advise according to what we see here.

And while I'm not sure who posted it, don't dismiss phone lines as having "low/safe/harmless" voltages.

Grabbing them while somebody calls will still make your eyes light up moderately well.

AMUN

Reply to
Amun

How important is the polarity of the wires? I have 2 telephone lines coming into the house and they are split to most locations. At the NID, there are 3 sets of wires going to the 3 floors in the house!

When I used my telephone polarity tester, only one of the locations shows 'correct' wiring.

BUT...all the jacks appear to be working correctly, including the ones which say 'incorrect' wiring.

Is this an issue or is it a case of 'if it ain't broke, don't fix it'?

Reply to
Rex's Mom

For a user terminal such as a phone or a modem polarity is not important at all. This is a balanced signal, so only voltage difference between the conductors in the pair matters. Keeping right polarity is still a good practice while installing phone wiring though.

Reply to
Dmitri(Cabling-Design.com

Thank you all for the responses.

The consensus seems to be that polarity for voice is not a major issue. BUT...the comment was then made 'when you feel up to it, you might want to correct it'.

So...next question, if I have followed the standards for 2 line hookup (R&G line 1, B&Y line 2), then how do I rewire to 'correct' the polarity?

Reply to
Rex's Mom

: > Pat Coghlan wrote: : >

: >> Rex's Mom wrote: : >>

: >>> How important is the polarity of the wires? I have 2 telephone lines : >>> coming into the house and they are split to most locations. At the : >>> NID, there are 3 sets of wires going to the 3 floors in the house! : >>>

: >>> When I used my telephone polarity tester, only one of the locations : >>> shows 'correct' wiring. : >>>

: >>> BUT...all the jacks appear to be working correctly, including the : >>> ones which say 'incorrect' wiring. : >>>

: >>> Is this an issue or is it a case of 'if it ain't broke, don't fix it'? : : Thank you all for the responses. : : The consensus seems to be that polarity for voice is not a : major issue. BUT...the comment was then made 'when you feel : up to it, you might want to correct it'. : : So...next question, if I have followed the standards for 2 : line hookup (R&G line 1, B&Y line 2), then how do I rewire : to 'correct' the polarity? : -- : : Rex's Mom

Actually, it's not hard. Since you have a polarity tester, simply reverse the two wires at each box showing reverse polarity. It sounds like you just split off at some point and attached the B & Y to a R & G, right? Simply remove the box cover or anywhere along the line, and interchange the two wires connected. Black will go where Yellow was and Yellow will go where Black was. Same with the Red & Green.

It sounds like you'd make a good telecom engineer! Happy chatting!

PopS

Reply to
Pop

: > > I meant 100V _/AC/._ : > >

: > > Pat Coghlan wrote: : > >

: > >> Rex's Mom wrote: : > >>

: > >>> How important is the polarity of the wires? I have 2 telephone lines : > >>> coming into the house and they are split to most locations. At the : > >>> NID, there are 3 sets of wires going to the 3 floors in the house! : > >>>

: > >>> When I used my telephone polarity tester, only one of the locations : > >>> shows 'correct' wiring. : > >>>

: > >>> BUT...all the jacks appear to be working correctly, including the : > >>> ones which say 'incorrect' wiring. : > >>>

: > >>> Is this an issue or is it a case of 'if it ain't broke, don't fix it'? : > : > Thank you all for the responses. : >

: > The consensus seems to be that polarity for voice is not a : > major issue. BUT...the comment was then made 'when you feel : > up to it, you might want to correct it'. : >

: > So...next question, if I have followed the standards for 2 : > line hookup (R&G line 1, B&Y line 2), then how do I rewire : > to 'correct' the polarity? : > -- : >

: > Rex's Mom : >

: : While going by "wire colors" is not 100% advisable. : As different wires may have different colors. : : If you have some sort of meter. : : Try reversing the red and green. : : Or the black and yellow. : : And see if the "meter" tells you it's okay. : : : These are very vague suggestions, but all we can do is advise according to : what we see here. : : And while I'm not sure who posted it, don't dismiss phone lines as having : "low/safe/harmless" voltages. : : Grabbing them while somebody calls will still make your eyes light up : moderately well. : : : AMUN : : LOL! It sure can! Actually, it can also be dangerous also during ring voltage. The ring generators are current limited, but can still supply enough current to damage the heart or brain if it should flow through them. One of the reasons rings stop/start is to prevent the muscle-clamping part of a shock from lasting long enough to kill because a person can't let go. That's not to mention the injury because the surprise shock causes one to all from a ladder, put an elbow through a window, stab yourself with the screw driver, and so on.

Regards,

Reply to
Pop

Please consider setting your newsreader to plain text reply. Some of us see this when you use HTML:

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I meant 100V AC.

Pat Coghlan wrote:

Rex's Mom wrote: How important is the polarity of the wires? I have 2 telephone lines coming into the house and they are split to most locations. At the NID, there are 3 sets of wires going to the 3 floors in the house! When I used my telephone polarity tester, only one of the locations shows 'correct' wiring. BUT...all the jacks appear to be working correctly, including the ones which say 'incorrect' wiring. Is this an issue or is it a case of 'if it ain't broke, don't fix it'? Maybe phones auto-correct for polarity.  It doesn't matter for ringing, since this is 100V DC, but I would expect that tip & ring must be connected properly - at least from what I remember from my basic telephone electronics seminar back in '81 :-)

Reply to
George

Most (but not necessarily 100%) of modern phones have diode bridges built in which, to use the words of another poster, "auto-correct" for polarity. If the installer has paid attention, wire color is important, but the actual tip-ring position on the jack is more important. Be aware that your jacks can have correct polarity and the modular cord connecting the phone to the jack can be inverted, especially if it was a homeowner who crimped the jacks on the ends of the cable.

Most of the old touch tone phones from the 70's (including non Western Electric) required the correct polarity or the touch tones didn't work. Later phones included the diodes.

The specification is still in place and there may be isolated pieces of equipment (PBX's Interfaces, certain modems, alarm system dialers, etc.) that still require correct polarity so there are benefits to getting it right.

Beachcomber

Reply to
Beachcomber

Pls see previous posts for details. See responses inline

Wow, Rex has one helluva mom! That's a compliment, BTW. That's an interesting setup, but I've seen many that were worse.

Just to clarify something: This IS only one phone number, right? I'm pretty sure it is from your postings, but ... we all know about ass-u-me-ing things when one shouldn't.

: : So, if I were to start reversing to get 'proper polarity' do : I have to reverse at all 'junctions'? If the answer is yes, : think I'll take a pass for the time being.

===> NO. But, depending on what you mean by "junctions":

Only do the reversals at one point per wall jack, and if possible, because of the several different daisy chains and parallels you have, try -very- hard to make the reversals right at the wires coming into the wall jack's screw terminals. A possible exception is when one jack goes also directly to another jack. If you reverse the wire pair coming in, it'll reverse it for both jacks. But if you reverse it where the wires go -out- to the telephone, then you'd have to do both of them.

I'll be honest with you, since you have sort of a bastardized system anyway, and it's working, or about to work, I don't think I'd worry about getting everything perfect.

You can actually think of the wires as hot and cold water pipes and you'll get the same exact answers. You've apparently already figured out that it's pins 3 and 4 of the jacks that you need to wires connected to; you just didn't know anything about polarities.

Consider this possibility: Are all (or most) of the reversed polarities on one of the cables coming from the NID? If so, reversing the wires at the NID would reverse everything that cable goes to.

: : But, I do thank you for the concise and precise answers you : have provided. : : BTW: Curiously, when I try to plug directly into the wall : jack, the modular plug does not go all the way in, but this : was the case when I first took the wall jack out of the : container before I had hooked it up. Seems to work better : with some cord versus other. However, this is not really an : issue as I don't NEED to connect a phone to the wall jack.

Sometimes the jacks can be either very stiff when first used, or messed up or made for specific cords. As long as it works and stays connected, I wouldn't worry about it. If you can't get anything to plug into it, and if you care, try looking into the open jack to see if there is a bent contact in there. That's the usual failure mechanism for jacks. It sounds like you're only using it for a junction box though, not a phone so if it's not broke ... ;-}

Here's one last piece of advice for you: The boxes should be mounted so that the jacks point downward. Lots of people like to put them upside down because they're easier to plug into, but it's not a good idea. They collect dust, flies and all sorts of things that fall into them if they're upside down. Been there, done it - found a crushed fly in one of the jacks shorting the whole system. Knocked out the fly, all worked fine!

PopS : : -- : : Rex's Mom : : :

Reply to
Pop

Yes Simply remove the box

Perhaps...all I know is I get the bit between my teeth and I won't let go till it works. Then....I try to make it work better and that's where the time gets eroded!

Yes to the splitting. The lines are split at the NID and then split at the internal jack(s) and then telephones are connected to the jack(s).

The one in question is a bit complex (user error/intention). Split at NID, split at jack (duplex wall jack) and, here's the complicated part, have also attached wire/cable, cord (not sure which is correct term) to the terminals on the wall jack and run the wire to the opposite end of the room in question. At that end, the wire is also split into a duplex wall jack which fits over an electric outlet (leaving the outlet available - great when the machine in question is a fax).

So, if I were to start reversing to get 'proper polarity' do I have to reverse at all 'junctions'? If the answer is yes, think I'll take a pass for the time being.

But, I do thank you for the concise and precise answers you have provided.

BTW: Curiously, when I try to plug directly into the wall jack, the modular plug does not go all the way in, but this was the case when I first took the wall jack out of the container before I had hooked it up. Seems to work better with some cord versus other. However, this is not really an issue as I don't NEED to connect a phone to the wall jack.

Reply to
Rex's Mom

had heard/read that the best bet is to take one phone for the line off the hook to avoid a ring.

don't do ladders!

Reply to
Rex's Mom

No inine: All top posted

Oh! Two lines adds a little complexity to the situation but helps some ,too. When you said "split" at the NID I ass-u-me'd you meant you split one phone line in two directions. Here's a site that might explain a lot for you:

formatting link
seem to have a grasp of the basics, so you should be all right. About every kind of phone line is covered there.

The introduction of the broadband modem however does add complexity to things if it's relevant to your original question. Broadband is digital, so I'm assuming it has nothing to do with your query because you've only discussed analog technology which only involves two wires, tip and ring, in order to work. If a digital phone line is involved though, and the digital goes to any telephones without an analog conversion, then something isn't going to fiunction, I'm pretty sure.

Look over the web site URL above; I think it'll help a lot.

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has several sections on different things.

I'd still be happy to assist you if you think you need it, but I'd have to have more clear and concise descriptions. At this point, I think you're back to "if it works, don't fix it".

Regards,

PopS

Reply to
Pop

and now see my responses inline. BTW - loved some of your comments and got quite a chortle from them.

Thank you. It seemed easier than trying to route it through the walls in a fully finished room.

strange question considering that I kept talking about splitting the r/g and b/y. Why would someone split if only one phone number. That's not a dig at you; I have only split when dealing with 2 numbers.

No...it is 2 separate telephone numbers. One is used for voice; the other is reserved for fax or dial-up internet. Haven't used the dial-up in ages, but before I got my wireless router it was the only option when I wasn't near the broadband modem.

since you're obviously intelligent, I am wondering if i was not sufficiently clear.

couldn't think of another word. the wires are split at each 'connection' point and that's what I meant. But your further comments clarified it for me.

I think I understand, but...see further.

couldn't agree more.

Nope...the reversed polarity is in at least 2 of the cables. If so,

given how long it took to complete the project, I am reticent to do anything further.

There has been a short in the 'extension' wire for a very long time and I finally decided to replace it. Have a friend who works for telco and he kept saying he'd come over and do it. He also said that, in his opinion/experience, the flat wire available at Radio Shack etc. does not split well and I should use the telco wire I was given by another telco repair guy. What he failed to tell me is that telco wire is much stiffer and does not lend itself to having a modular plug crimped onto it. I learned this when I saw a telco truck on the street and stopped him and asked after going through almost an entire package of modular plugs!

So...I did a bit of work, hit a problem, paused waiting for my friend, went back to it. ad nauseum.

The main reason I was asking about the polarity was I was wondering if it was contributing to the shorting problem.

Now you tell me. :-D. Guess I'll check that out!

I guess a fly in the jack is better than bats in the belfry.

Reply to
Rex's Mom

.... : > Great Pyrenese are even better! : While I do like them, still prefer my Labs! .... Smartest, most loyal dog I ever had was a Newfie/Lab mix; looked mostly like a large lab with with "funny" fur. Glad you're a fellow animal lover!

Best of luck with your system there.

I'd be curious to know what you plan to do ;-}. let 'er lie or what? Seriously, this thread's gotten pretty hard to read. If you're still looking for info it might be best to start over with a new quest. Just my opinion.

PopS

PopS

Reply to
Pop

Pop wrote: inline to your most recent

had been to that site prior to starting my postings here and it wasn't telling me what I needed to know, but who knows what the original question was anyway. I have bookmarked it for reference.

sorry about the broadband modem mention...it is a red herring. I only mentioned it to indicate why/when the second line is used. (p.s. it has sometimes also been necessary when the first line dies and I get telco to auto transfer calls from first line while they get around to the necessary repair)

all lines are strictly analog.

no, I think at this point you have answered all my queries plus supplied some invaluable information. Will turn my handyman attention to other things. thank you for your help and patience.

While I do like them, still prefer my Labs!

Reply to
Rex's Mom

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