Communications Wiring FAQ

New Construction Wiring

Are you thinking about or already building a new home? Wiring it for automation and distributed media is much more cost effective when done during new construction. You only have one opportunity to do this well, and that is before the sheet rock or other wall coverings are installed.

First decision is: Hire an Integration Pro? Do it Yourself? If the latter, be prepared to spend a lot of time, and accept that you will make errors that will take at least time to resolve. For most, hire a pro. If you do decide to DIY, read on.

Make sure you consult with your building contractor (if that is not you) to make sure that you can do any of the wiring yourself, or can even contract the work to an Integration Pro. Make sure that you are doing everything with approval of the local inspection code authority as they have final say on what you can / can't do and how to do it.

During system (and home) design, it is important to determine a central equipment closet. Ideals are centrally located (to reduce wire run lengths), ease of access (you will be spending a lot of time plugging things in...). If your myServer Server and Media servers are also located there, then put it out of earshot of the Theater room, and have physical wire run access to all points. If you make the location not noise important, then your PC hardware will be less expensive as noise free costs more. Make sure the wiring closet has cool air circulation to keep equipment safe from overheating.

All telephone, ethernet, video distribution, IR distribution, alarm, One Wire runs (for home automation), and audio should be located here.

Here is an excellent overview: How to Wire

Here is another excellent wiring related document including spreadsheets for your organization Cocoontech wiring guide

Run at least 2 RG6 quad shield to all rooms (In / Out or In / In video capability). Run at least one Cat 5 on each major side of each room (this can be for phone, LAN, IR, One wire, etc.). Use Cat 5 instead of Cat 3 (allows versatle use without much added expense).

Run many RG6 runs to the roof for satellite (I should have run 7 runs) if there aren't other content availability like digital cable. If in snowy area, add wires to power a satellite dish heater. OTA antenna rotator control wires.

Use punch down blocks for alarm (hard wire is preferable if new construction), LAN, IR, One Wire.

Home Depot has Leviton structured media panels that aren't too much money and help clean up the install.

Speaker wire to prominent rooms (I use 12 gauge stranded for longer length runs, 14 for shorter runs or ambiance speakers). Don't forget about outside speaker runs.

Zone heating low voltage wiring (automation of heat system). Cat 5 to thermostat (for automation serial control thermostats like the RSC)

Alarm system wiring including motion sensors, glass breaks, door / window contacts (including garage doors), fire detectors, water level detectors (mud room / utility room / bathroom).

Deluxe things: low voltage wiring to power awnings, motion sensor low voltage to detect room navigation (switches lights / audio appropriately).

More Info:

I'd suggest at least 2 cat5 wires and 2 rg6 wires, all "home run" to a head end or equipment closet, from 2 prominent points in each room (so, at last 4 cat5 and 4 rg6 in total per room, EACH going directly to the head end). In places where you'll have a lot of office- or computer-type equipment, or you'll have a lot of home A/V equipment, I'd run more than that. It sounds excessive, but it isn't, believe me - especially when you start dealing with networked printers, DSL modems, channel modulators, etc.! You can buy bundled cable with 2 cat5, 2 rg6, and even 2 fiber optic wires within one sheath, which is really handy.

I'd recommend also doing a home run of cat5 from just inside the door to each major room; that way, if you want to put in keypads or something later, the wires are already there. You may want to mark where the wires are terminated with a tiny bump in the wall so you can find them easily in the future. Suggested is to put a run of cat5 to near the door in the bathroom because Hey, you never know.

Another thing to keep in mind is to make sure that the low voltage wires are kept well separate from the high voltage wires, or you could get interference.

Most power line lighting control systems require to have a third wire between the switch and the light itself, so keep that in mind for planning. Also, if you're planning on being able to decrease the volume of speakers within a room from a wall-mounted knob, you may need to first run the speaker cable past that knob before it leads to the speakers themselves (unless it's otherwise controlled at the head end).

If your electrician normally does high-voltage work and is not that familiar with low voltage wires, make sure that he or she does not install them in the wall of a room and then CUT THEM, assuming he or she can attach them later to wires from the central location. You're probably thinking, what idiot would do that? but it does happen, so it's worth just double-checking with your contractor.

Don't forget thermostat wires (RS-485 is best which requires CAT5 from wall unit to furnace unit) and alarm wires. CAT5 from sensors to closet.

Finally, a word to the wise is to MAP EVERYTHING before the walls are closed. It's easy to put off doing it until it's too late. Once you've mapped it... don't lose the map! Ideally, you should mark all wires as they are being installed. A wire marking printer is a great investment (about $100 for low end units that work fine). If you are pushed for time and can't mark the wires, fear not as a signal tracing transmitter / receiver pair can find wires almost as fast after they are all installed (about $100 from Home Depot).

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Quick tip: make a video recording of every wire in every room before the insulation / drywall go up. Put a tape measure on the floor to give reference to location of wire bundles.

Also, you might also want to put an empty tube from basement to attic and put a pull cord in it. No matter what, you will forget to wire something that 6 months later will take more time to route than a whole room of wire during construction.

Talk to the plumber and heating contractor on their routing plan so you don't get in the way. Ideally, low voltage goes in after plumbing, heating and right after or during high voltage wiring.

If you need to cross high voltage, keep as much distance as possible and cross at right angles. Don't make neat bundles of high and low voltage!

In my walkout basement I wanted drywall finished ceilings since I hate drop ceilings. This makes after the fact wiring and maintenance very difficult. The work around was to leave a 5 inch gap without ceiling drywall between wall and ceiling. "J" channel was put on the raw ceiling drywall edge to make a finished line. Tongue and Groove wood boards were installed with screws to provide an architectural look and as a plus- a wire chase around the room!

Serial Cables

Serial cables come "straight through" and "null modem". Make sure to select the appropriate cable for the hardware you are trying to control. This is the number one reason why folks have difficulty with serial controlled devices. Cinemar sells the appropriate serial cable for the most popular equipment that Cinemar supports to save time to get the correct one.

The PC end of the cable is called a "DB9 (nine pin) Female" The equipment end can be either a Female or Male. Serial cables come in all combinations of Female / Male and straight through and Null Modem. You can also purchase an adapter to make a straight through cable a null modem cable (and visa versa). You can also purchase an adapter to change the sex of one end.

Many times, you have your PC located in a room distant from the RS232 device that it needs to control. When you have prewired Cat5 cable, you can make adapters that convert a network wire to a serial wire. Be careful NOT to plug a serial cable into an ethernet LAN.

Cable Info

How to use CAT5 cable as a serial cable:

Build a Cable Adapter


Typical is pin 2,3 and 5 on the DB9. (on the db9)
2 is Tx 
3 is Rx 
5 is Ground

RJ-45 DB-9 M/F 
1 (Blue) DSR(out) 6
2 (Orange) CTS(out) 8 
3 (Black) GRD 5 
4 (Red) TX(in) 3 
5 (Green) RX(out) 2 
6 (Yellow) DCD(out) 1 
7 (Brown) RTS(in) 7 
8 (Gray) DTR(in) 4 
out – signal is from UniGuard
in – signal from Host Equipment

I really does not matter what wire pairs you use in the piece of cat 5, as long as you are consistant end for end.

If you are using one of those RJ45 to DB9 general adaptors (the one that you plug the wires into), then just make sure you get the signal on those pins.

Common myServer supported devices and their cable types:

Russound Cav6.6: Straight through (flip the switch on the rear of the unit to enable serial communication)

Sony CX777ES: Null Modem Cable

ELK M1Gold: DB9 Male to DB9 Female. Pin 2 to Pin2, Pin 3 to Pin 3, Pin 5 to Pin 5 (straight through)

HAI Security panels: requires RJ11 connector to DB9. Recommended is to purchase this from HAI.

Connecting a Sony CX777ES changer to myServer Server PC

Here is the best reliable connection plan myServer ClientPC <> ethernet <> gigabit LAN / router <> MLServer3 PC running CX777ES plugin and myMovies app and database <> com port <> proper serial cable <> sony CX777ES changer.

Here is a semi wireless but reliable setup: myServer 802.11G ClientPC <> wireless LAN <> gigabit LAN / router <> MLServer3 PC running CX777ES plugin and myMovies App and database <> ethernet <> global Cache w/ serial port <> proper serial cable <> sony CX777ES changer.

Here is a "fully" wireless but maybe not perfectly reliable setup: myServer 802.11G ClientPC <> wireless LAN <> gigabit LAN / router <> MLServer3 PC running CX777ES plugin and myMovies App and database <> ethernet <> wireless access point <> ethernet <> wireless access point <> ethernet <> global Cache w/ serial port <> proper serial cable <> sony CX777ES changer.