Wiring closet

A wiring cupboard is a small room commonly found in institutional buildings, such as schools and offices, where electrical connections are made. While they are used for many purposes, their most common use is for computer networking where it may be called a premises wire distribution room (PWD room). Many types of network connections place limits on the distance between end user equipment, such as personal computers, and network access devices, such as routers. These restrictions might require multiple wiring cupboards on each floor of a large building.

The inside of a wiring closet at a small public university. Visible are an optical fiber switch (top), a 66-type punch block (left), and two 110-type punch blocks (right, bottom). The orange conduit contains optical fiber cable.

An equipment box of the type that might be found in a wiring cupboard

Equipment that may be found in a wiring closet includes:

• Alarm systems
• Circuit breaker panels
• Video systems, such as cable TV and closed-circuit television systems
• Ethernet routers, Network switches, Firewalls
• Fiber optic terminations
• Patch panels
• Telephone punch blocks
• Wireless access points