This is a breakdown of the materials needed for our hypothetical installation. The job is for 30 double voice/data outlets.

First we need a cabinet. The size of this depends upon the amount of space required for patch panels, hubs, the customers equipment, and how much room the customer has. Cabinets come in a range of sizes measured in 'Units' or 'U', one 'U' is about 1.7 inches or 44.54mm. In our hypothetical installation the cabinet will need to house:

 

2 x 32 way patch panels to terminate the 60 cables @ 2U each = 4U
1 x 32 way patch panel to terminate the telephone multi-core = 2U
2 x 16 port hubs @ 1U each = 2U
5 x cable management panels @ 1U each = 5U
Space required by client to house other networking equipment = 6U
Space for future expansion = 6U
Total = 25U

So a 27U cabinet will do nicely.
 
 
 
 

6 x boxes of Cat 5e cable - A box of cable is 305m and we need about 1800m so six boxes would do, but as the cable is fairly inexpensive, buying eight boxes means we can pull in more cables each time which makes the installation quicker. It also covers the amount of wastage which would be expected unless you can cut each cable to exactly the right length at every outlet.

30 x double Cat 5e outlets and back boxes. Some systems comprise of single outlet modules which clip into single gang or two gang faceplates, in this case 60 modules would be required with 30 single faceplates.

30 x PBX master telephone adapters - In the UK these are used to change the BT style telephone plugs to RJ45's so they can be used on the structured cabling system. Inside the PBX master adapters are the components that you find in a normal BT wall socket, these enable analogue telephones to ring. If the telephone system is digital it may not need these components so we could buy secondary adapters instead. Some customers may have both types of phones so you need to check, also, any external lines will need PSTN master adapters, these are like normal PBX masters but with surge arrestors fitted.

60 x patch leads (30 x 1.5m, 30 x 2m) - 30 for patching the network hubs and 30 for patching in the phones. Various lengths are available and it depends on the cabinet layout to which lengths are bought.

30 x 3m fly leads - these are the same as patch leads and are used to connect from the wall outlets to the PC's. We don't need any for the telephones as they have their own leads.

That about covers it apart from some trunking, cable ties and a method of labelling the system.

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