I'm an Electrician, but data is still a little bit oogah-boogah to me. So here's my question; I ordered a second phone line for my house/shop. After the phone company tech left, I went into the box to hook up the house wiring. Pretty straight foward stuff, or so I thought. Black, red, yellow, and green hooked to each other, red and green IIRC for line 1, and yellow and black for line 2. It was consistent from the box to all the phone jacks in the house (same colors). The problem is, line 2 never would make or receive calls, and line 1 would show up on the phone when either line 1 or 2 was activated. I did some pretty extensive testing with a cell phone with CID, so I am absolutely positive above the phone line configuration. I also tested a couple different 2-line phones to eliminate the possibility of device malfunction. From what I know of electrical, I am guessing maybe a crossed circuit somewhere in the house. Does this sound possible, and can I use an electrical circuit tracer and ohmmeter to troubleshoot, or am I way off base? Thanks in advance for any assistance. A
Troubleshooting Telephone Wiring
Seven-Delta-FortyOne
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I'm an Electrician, but data is still a little bit oogah-boogah to me. So here's my question; I ordered a second phone line for my house/shop. After the phone company tech left, I went into the box to hook up the house wiring. Pretty straight foward stuff, or so I thought. Black, red, yellow, and green hooked to each other, red and green IIRC for line 1, and yellow and black for line 2. It was consistent from the box to all the phone jacks in the house (same colors). The problem is, line 2 never would make or receive calls, and line 1 would show up on the phone when either line 1 or 2 was activated. I did some pretty extensive testing with a cell phone with CID, so I am absolutely positive above the phone line configuration. I also tested a couple different 2-line phones to eliminate the possibility of device malfunction. From what I know of electrical, I am guessing maybe a crossed circuit somewhere in the house. Does this sound possible, and can I use an electrical circuit tracer and ohmmeter to troubleshoot, or am I way off base? Thanks in advance for any assistance. A
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Perhaps you just didn't get a second line......... you got a second line that rolls over from the first if it's busy.
Check the cord between the phone and the wall jack. Make sure it's a 4-conductor.
Ohmmeters are pretty much useless in telecom TSing. You need a tone set and a butt set to start with.
Check the cord between the phone and the wall jack. Make sure it's a 4-conductor.
Ohmmeters are pretty much useless in telecom TSing. You need a tone set and a butt set to start with.
Thanks, 480. I tested the line at jacks in the outside box, and they were separate and functioning, but inside they went haywire. That's why I figured it was my wiring.
Open circuit [on hook] voltage should be about 4 x 14 = 56 vdc. Four lead acid batteries being charged.
Off hook should be two or three volts.
Short circuit current should be around 0.17 Adc.
These numbers depend on distance from the office.
Also, apparently phone lines in a house are wired in a loop so a single broken conductor does not put you out of service.
You may not be able to trust wire colors. Test with an ohmmeter or a voltmeter and use an extension cord as a very long test lead.
Off hook should be two or three volts.
Short circuit current should be around 0.17 Adc.
These numbers depend on distance from the office.
Also, apparently phone lines in a house are wired in a loop so a single broken conductor does not put you out of service.
You may not be able to trust wire colors. Test with an ohmmeter or a voltmeter and use an extension cord as a very long test lead.
Is this just a standalone two-line phone plugged into a two-line [two-pair] jack?
At the jack, Line 1 is normally the inner pair and Line 2 is the outer pair.
If you’re sure it’s not a phone programming/setup issue and the jack wiring is correct, have you also checked to see if maybe the flat cord [Silver Satin] that goes between the wall jack and phone is the correct straight or reverse wired type as called for by the phone manufacturer?
At the jack, Line 1 is normally the inner pair and Line 2 is the outer pair.
If you’re sure it’s not a phone programming/setup issue and the jack wiring is correct, have you also checked to see if maybe the flat cord [Silver Satin] that goes between the wall jack and phone is the correct straight or reverse wired type as called for by the phone manufacturer?
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That's Old Skool wiring. I've been running a HR for each station for 18 years.
Just in case you don't have it straightened out yet, how about some very elementary troubleshooting?
Check for voltage on both pairs at your jack inside the house. Then disconnect yellow/black at the outside box and check again. You should have voltage only on red/green.
Reconnect yellow/black, disconnect red/green and check again. You should have voltage only on yellow/black.
Disconnect everything and check for continuity between all possible pair combinations of the four wires. There should be none.
If indeed the two lines work properly at the outside box but not inside, one of those tests will fail.
Excelent info all. Thank you very much. I think I'll do some elementary troubleshooting tomorrow. I don't have a butt set or toner, so if I can't figure it out, I think it might be time to call in a data guy.
House hold telephone systems are quite possibly the easiest thing to troubleshoot. You checked the incoming lines and they checkout, now trace the rest of the wires.
Problems with phones are always elementary, the only time weird stuff happens is when the idiot installing a sound system punches out a phone line as a keypad and burns 4 hours trying to figure it out....not that it every happened to me. :laughing:
Problems with phones are always elementary, the only time weird stuff happens is when the idiot installing a sound system punches out a phone line as a keypad and burns 4 hours trying to figure it out....not that it every happened to me. :laughing:
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This is a very common problem. What happens is that somewhere along the chain of jacks, someone pairs the green with the black and then they pair the red with the yellow to ensure redundancy or to quickly fix a problem without any troubleshooting.
The first thing that I would do is to open every single jack and disconnect all of the wires from each jack so that you have raw unterminated ends coming out of the wall. Also disconnect the wires leading from the telephone network box.
Next, I would use a tester or multimeter to check for shorts by testing each of the 4 wires against each other. e.g. hold one lead on the red and touch the other three wires individually and then go on to the black, the green, and so-forth. You'll pair up most of the wires more than once but that's just a sure way of making sure that there isn't anything shorted or connected together.
If you detect a short, chances are that there is a phone jack somewhere else in the house that you don't know about. If you can't find it, then maybe you can isolate the sections of the chain where the lines are shorted and hopefully you can get your second line service where you need it without it going through the whole house.
The first thing that I would do is to open every single jack and disconnect all of the wires from each jack so that you have raw unterminated ends coming out of the wall. Also disconnect the wires leading from the telephone network box.
Next, I would use a tester or multimeter to check for shorts by testing each of the 4 wires against each other. e.g. hold one lead on the red and touch the other three wires individually and then go on to the black, the green, and so-forth. You'll pair up most of the wires more than once but that's just a sure way of making sure that there isn't anything shorted or connected together.
If you detect a short, chances are that there is a phone jack somewhere else in the house that you don't know about. If you can't find it, then maybe you can isolate the sections of the chain where the lines are shorted and hopefully you can get your second line service where you need it without it going through the whole house.
Four wires and two jacks is 8 separate ohm tests. That should go quick.
You also might want to test for shorts to ground but the phone lines may be floating with respect to ground. 10 tests.
With this many wires keeping track may be a problem.
Don't stop at the first problem you find.
You also might want to test for shorts to ground but the phone lines may be floating with respect to ground. 10 tests.
With this many wires keeping track may be a problem.
Don't stop at the first problem you find.
IMO, using a standard VOM to test for a possible intermittent fault on Telco/POTS is normally a waste of time. You really should use a meter that can at least perform a kick test. This is much like using a megohm meter on motors and electrical conductors to find a fault that a regular DMM/VOM would miss.
These days you can buy a cheap toner and probe kit for around $50.00. Even if you only do telephone once a year, I think it would still pay for itself, just for these types of situations around the house.
These days you can buy a cheap toner and probe kit for around $50.00. Even if you only do telephone once a year, I think it would still pay for itself, just for these types of situations around the house.
Never heard of it.
http://www.freepatentsonline.com/7295654.html
I must be obsolete. When did that happen?
I guess you can also use a C-meter if you have one. You might get 100 pF per foot of cable.
Excessive capacitance shouldn't affect the DC readings but it might kill the audio frequencies. And the TelCo equipment might not like it.
Thanks. I wasn't sure if standard tests like what I would perform on a line voltage system would work, but it sounds like it does. I appreciate all the help. If I figure this one out, maybe data won't seem so strange to me.
BTW, Why might my standard ohmmeter not work on data lines?Gettinby, I always enjoy reading your posts on electrical. They're always technical and informative. Thanks.
They work just fine if you know what you're looking for, a toner and probe is just an excellent addition. I wouldn't want to walk into any troubleshooting scenario without either one.
How many of you guys have had a real noggin scratcher when it comes to telephone troubleshooting? Any good stories out there?
You're welcome.
The GI bill paid for some of my schooling so it's your tax dollars at work. :laughing:
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