DSL/Phone Wiring

Starting off the New Year right is one of my priorities in life. For me, that often means implementing a fun project, typically involving technology and/or something around the house, car, bicycle or all of the above. This year was no exception and I decided that it was time to put together all the parts I had accumulated over the past several months to update my telephone wiring. To be clear, this is *not* about ripping out all the wiring behind the walls in my house. It's just to improve the "visible" stuff in the unfinished basement utility room area. There were 4 primary goals for this project:

1. Clean up the spider web phone wiring mess just inside the house.
2. Directly connect a DSL jack to Telco Network Interface Device (NID).
3. Implement whole house phone line surge protection.
4. Clean up the alarm system phone line connection.

In addition to these enumerated goals, a side benefit was to gain knowledge and experience about proper wiring supplies, techniques and equipment.

It helps to understand the solutions if the specific problem areas are described in more detail. The following paragraphs will do this ... check them out to see if you may have some of the same issues or concerns about "doing it right" (or at least "doing it better than it was" ).

POTS (Plain Old Telephone System) Wiring
As was common in the mid 90's when this house was built, standard 4 wire (Red, Green, Yellow, Black) telephone cable was installed. Not very resistant to cross talk and capable of generating quite a bit of noise, I was uncomfortable with using it for my DSL connection to the Telco (Qwest, in this case) NID outside the house. The inside wiring was done in the "Star" configuration where each wire pair was connected to the NID and then run directly to a room (or area) of the house. In the destination area, it might be hooked up in series (daisy chained) but the star technique still allowed for isolation of connection problems to a small number of phone jacks. Good idea, but it felt like a better idea to bring a single line into the house (and see the DSL section, below) for a very short distance, subsequently distributing it via multiple cables to the various rooms.

DSL
The aDSL (Asymmetric Digital Subscriber Line) 7Mbps connection had been working OK but there were occasional times (confirmed by Qwest technical support) when somewhat high "dropped bit" rates were encountered. Not knowing the source of this, it felt important to do the best possible job of eliminating local house wiring as an issue. For this reason, and in tandem with the goal to bring a single cable set in from the NID, 4-UTP (Unshielded Twisted Pair) Cat 5E cable was chosen to bring the connection in to the house. While good cable alone doesn't make for a good connection (connectors, jacks, proximity to power and noise carrying lines and installation technique are all contributors), using the correct cable *is* a key requirement for a good, solid connection and it's a straightforward thing to do. The idea was to run as directly as possible from the NID to a jack specifically used only for connecting to the DSL modem.

The "normal" DSL setup for a residence is usually done on the cheap and often consists only of connecting Telco supplied low pass filters to all the active "phone" connections to keep the high frequency DSL signal noise out of voice conversations and prevent the low frequency (voice and DC) signals from attenuating the DSL signal. Not wanting to put a filter on each phone in the house, the original wiring job fed the input lines to a pair of DSL filters before distribution to the rest of the house (with the DSL line running directly out to the NID). These small filters, however, are not designed to operate this way and may be overloaded, depending on the number of phones in the house that simultaneously ring. The alternative chosen was to implement what's called a DSL-POTS splitter. This device is mounted (depending on its specific design) at the NID or just inside the building and it filters and splits the input line's signal into its voice and DSL components. It does cost a bit ($35 or so for this one) but it provides a relatively cheap and elegant alternative to appending a filter to each phone. In this case, the Wilcom PS-15-I3S (mounts inside the residence) xDSL-POTS splitter was chosen and two were installed to allow for possible future easy movement of the DSL connection to Line 2 (from the standard Line 1) as well as the option to have 2 independent DSL lines active simultaneously. Another benefit is the redundancy factor--for single line DSL, should one of the splitters fail, it would be a very quick procedure to switch to the other, avoiding more than minimal down time.

Surge Protection
Similar to the issue (see above) regarding DSL/voice filters, the proliferation of phone line surge protection devices was something that needed addressing. Another good argument for bringing a single set of wires into the house from Telco, the idea was to run them through a surge protection device *before* distribution through the rest of the house phone wiring. The device chosen to accomplish this was the Open House ChannelPlus Telephone Entry Module (model H611). The H611 is designed to mount in a service center enclosure box (Open House model H318 used here) and provide surge protection for up to 4 incoming Tip/Ring pairs. In addition, it provides an RJ-31X jack to allow line seizure capability for an alarm system. Since the DSL line bypasses the voice line surge protection provided by the H611, a separate, surge protection device (TrippLite's Traveler 100Bt) was added at the DSL jack to protect the DSL modem (and downstream devices). Simple, effective (it is hoped) and now the whole house is protected from some degree of line surge without having to incorporate multiple surge protection devices.

Alarm System
While the alarm system (Rokonet Wisdom) was a DIY home project, it works very well and is designed to seize the phone line to call out to user programmed phone numbers (ostensibly to an alarm monitoring service but, for this system, just my cell phone). In order to do this, the alarm system must be connected as the first "phone" in system and the RJ-31X jack is designed to make that easy to do. The challenge here was to take out the old 4 wire cable connecting the alarm system and connect it to the H611's RJ-31X jack with standard (3-UTP) 24 gauge twisted pair wiring.

In summary, the problems above were to be addressed and the implementation accomplished is described below. Pictures of the detailed connections in the H318 Service Center Enclosure tell the story.


This picture shows the white H318 Service Center Enclosure box mounted in its final location between two wall studs in the basement utility room. The two black components mounted near the top of the box are the Wilcom PS-15-I3S DSL-POTS splitters for Line 1 and Line 2, respectively. The horizontal rectangular unit below the splitters is the H611 Telephone Entry Module. The blue Cat 5E cable entering the Enclosure at the top left side carries the Line 1 and Line 2 wires from the Telco Network Interface Device outside the house. The other blue Cat 5E cable exits the Enclosure at the top right side and goes directly to the DSL modem wall jack.

The leftmost white cable (on the H611) is a Cat 3 UTP from the "Phone" outputs of the two splitters and it connects via the H611's 110 punchdown connector for (input from the CO) Tip and Ring on Lines 1 and 2.

The middle white cable is another Cat 3 UTP connected to the H611's RJ-31X connector and it runs to the alarm system in the upstairs entryway to the house.

The rightmost white cable leaving the H611 consists of the surge protected Line 1 and Line 2 outputs from the H611 and it runs up and to the left of the Enclosure where it connects to the rest of the house's phone wiring.

Finally, the green wire running horizontally across the top of the Enclosure is simply a 10 gauge ground wire.


This is a closeup of the Open House H611 Telephone Entry Module. Here you can see (from left to right) the 110 connector for lines 1-4 (note that lines 1 and 2 are connected), the RJ-45 telephone disconnect plug, the RJ-31X alarm connector (at the bottom) and the house telephone output on the right side with Line 1 and Line 2 connected via the RJ-45 plug (which is connected in parallel to the alternative output 110 connector). For maximum connection flexibility, RJ-45/RJ-11 plugs were used wherever the option was available. Note the "Surge Warning" lights associated with each of up to 4 telephone lines that the H611 might be protecting. Each line is protected to 50 Joules and 4000 Amps. If the surge level is high enough, surge protection will be lost and the surge event will be shown as an illuminated LED associated with the appropriate line(s). Repair or replacement of the H611 module would then be required. Regarding connecting wires to the 110 connector--be sure to invest in a 110 punch down tool for this task. The 110 is a fairly sophisticated Insulation Displacement Connection (IDC) system and trying to get by with, for example, a screwdriver and/or needle nose pliers is unlikely to seat the wire properly, resulting in damaged contacts and possible future failure of the connected phone line(s). Finally, the module's RJ-45 jacks are wired to the TIA T568A standard.

The H611 module connects to the Service Enclosure with metal tabs in the back designed to fit the vertical columns of device mounting holes in the Enclosure.


This picture shows the Wilcom xDSL-POTS splitters mounted and connected in the Service Enclosure. The two units are facing each other to allow use of the RJ connections while minimizing the wire length needed as Line 1 and Line 2 are broken out from their respective cables to be sent to the individual signal splitter devices. The splitter on the left handles Line 1, the one on the right handles Line 2. Since these devices are not designed to mount directly into the Enclosure's pre-drilled holes, Velcro was used to attach them and to give some additional flexibility regarding precise location.

Testing
Integrity of the wiring was verified by inspection and by alternating the Line 1 supplied DSL signal between both the Line 1 and Line 2 splitters. Given this setup utilizing the RJ plug connections, line swapping to accomplish this test was trivial. Additionally, although this residence does not currently have regular POTS service from Qwest, a Phone Labs Dock-N-Talk was attached at the Network Interface Device to provide Tip and Ring in parallel with the DSL signal from the Telco. The phones and alarm system in the house were successful at dialing out. But full confidence in the alarm's line seizure capability will not be achieved until such time as regular Telco service can be used to verify it. Most DIYer's working on this kind of project probably have regular Telco phone service so that test is something that will normally be easily accomplished and it should not be neglected.


Finally, the new Service Enclosure all buttoned up and operating as planned. Much neater looking than the random wires that were floating around in the basement. For future reference, all device documentation as well as a rough schematic and URL reference to this blog are included in an envelope inside the Service Enclosure.

It is hoped that the information presented here is useful to others that may be mulling over the issues of telephone line surge protection, DSL/POTS performance and possible problems with handling an alarm system's dialing requirements. Again, this is just what one individual did and there may be better solutions ... but perhaps it's a good starting point.

All comments are welcome and please don't be put off because comments are reviewed before appearing in the article.