By Bob Catanzarite
The CWP or Central Wiring Panel - Chapter 1
Sorry - this page takes a bit long to load with a dialup connection! It has a lot of content and photos.
There are several suppliers that make prefabricated CWP's. An example of just some of them are shown in the photos below.
The prefab CWP's are fine products and may be just the ticket for you. On the Links page I have links to some of these suppliers. I chose to build my own CWP for a couple of reasons. The prefabs were too expensive. And even though they generally tried to make their CWP's re-configurable - I didn't see where they really were as configurable as I wanted. For example, I already had an RCA cable modem and a Linksys router and a Netgear 8-port switch. I couldn't find a prefab CWP that would accommodate all of these devices. Or, for that matter, any of them. So I built my own.
My Homebrew Central Wiring Panel
If you choose to build your own start by planning. What wiring type have you chosen to include in your structured wiring system? How many outlets have you chosen to install in your home? How many cables for each type of wiring will be running into the CWP?
In my case I chose to install Data, Video and Telephone. So what do you want to do with each of these wiring types?
Data - I have 8 outlet plates with each outlet plate having 2 Data ports. So I'll have a total of 16 CAT5 data lines coming into the CWP for data. I want to use switches instead of hubs for the data network. I already have a Netgear 8-port Fast Ethernet switch. Ill seed a second one to feed all of the 16 data ports. I need to have provisions for my Motorola Cable Modem and my Linksys router with 4-port switch. See the Wiring Diagrams page for an Overall Wiring Diagram for details.
Video - I have 8 outlet plates with each outlet having 2 video ports. So I'll have 16 RG6/U QS (Quad Shielded) cables coming into the CWP for video. I will be using CATV (Cable TV) for my main source of TV. I want to be able to accommodate DSS (Satellite) in the future. I want to have the option of adding an antenna as a backup. So, I'll need two 8-way video splitters. I'll need a video amplifier, maybe 2 of them, to make up for the signal losses in the 8-way splitters and the long video cable runs. See the page on Compensating for Video Losses. And see the Wiring Diagrams page for an Overall Wiring Diagram for details.
Telephone -I have 8 outlet plates with each outlet having 2 phone ports and each port has 2 phone lines. I have one CAT5 cable that feeds both of these phone ports. So I'll have a total of 8 CAT5 cables coming in for telephone. Nothing fancy here - just 8 outlets with 4 phone lines each. I'll need more than one 66 punchdown block for this. See the Wiring Diagrams page for an Overall Wiring Diagram for details. See the CWP - Chapter 2 page for more on punchdown blocks.
You have to come up with a rough estimate of how much space you'll need in the CWP. So, make a floorplan for the CWP. My CWP floorplan is shown below on the left. Click on the diagram for a larger PDF image. This is just meant to be rough sketch although mine was drawn to scale using QuickCAD from AutoDesk.
For the basic enclosure of the CWP I chose to use 2 standard Electrical Load Centers that you can buy at any good hardware store or electrical distributor. What I used were 2 Siemens G2020MB1100CU 100 Amp Load Center that I bought from my local Lowes Hardware for $65 each. See the photo above on the right. Now this came with a door like front panel (removed in the photo above) with spaces for 20 circuit breakers and inside had all the wiring provisions to mount and wire these 20 circuit breakers. All I needed from this whole thing was the basic enclosure so you can use any Load Center that is about the size that you'll need. So I just removed the door and all the internal electrical wiring parts. Even though I ended up throwing a lot of this load center away, getting the basic enclosure for $65 I thought was a bargain and was easy to buy. One of the other really nice things about using a Load Center for the CWP enclosure were the knock-out holes it had in it for attaching the electrical conduits.
This Load Center enclosure is build complete out of steel. In order to give yourself an easier to work with mounting surface for all of the things you'll be putting in this enclosure I would recommend making and installing a plywood back plate. I made mine out of 1/2" plywood and mounted it to the enclosure using four 1/4x20 bolts, nuts and washers acting as a standoff to raise the plywood slightly away from the steel back of the enclosure. Leave about 1" of spacing between the outside edges of the plywood panel and the inside walls of the Load Center. This plywood back plate makes it much easier to attach and later on move things.
Mount the enclosure to the wall. I chose to surface mount mine (mount it ON TO the wall instead of INSIDE the wall). If your flush mounting yours then your most likely going to be doing this during the rough-in and before the drywall goes up. If your going to use electrical conduit to bring all the wiring into the CWP, install the conduit. I chose to use conduit more for aesthetics reasons. I also chose to have separate conduits for telephone, video, data, AC power and feeder cables. This makes 5 conduits total. I used PVC conduit with the trade sizes of 2 1/2 (~ 2 7/8" O.D.) and 1 1/2 (~1 15/16" O.D.) The larger 2 1/2 size was used for the video cables due to the larger cable bundle diameter of those cables. I used the 1 1/2 size for everything else. I made the conduits long enough to extend through the ceiling and up into the attic about about 12". Then, up in the attic, I added 90º elbows on top of the conduit so that the cables weren't making such a sharp, tight bend as they go into the conduit. See the photo below on the left showing how the conduits extend up into the attic..
A different view of the CWP. The 9' ceilings make the CWP appear to be mounted low on the wall.
Add some provisions into the CWP for AC power. You'll likely to have several devices in the CWP that need AC power and some of them are likely to have the large transformers that have to plug directly into the AC receptacle. I chose to mount my AC outlets OUTSIDE of the CWP to help keep some spacing between the structured wiring cables and the AC power lines. You can see from the photo above on the right how I did mine. Hidden behind the 6 outlet surge protected outlet expander is a 2 outlet utility box mounted to the side of the enclosure on the left. The AC power for this utility outlet box comes in through the conduit for AC Power and is hard wired into the utility box. This utility outlet box was a metallic box and has the AC ground wire connected to it which also connected the entire CWP enclosure to ground. Then to get additional outlets I wedged in a 6 outlet power strip below the utility outlet box. Just be creative.