Punch down block, also called as cross-connect block, terminating block, or connecting block, is a type of terminal strip that connects one group of wires to another group of wires through a system of metal pegs that the wires are attached to, often used in telecommunications closets that support LAN(Local Area Network). Punch down blocks are the predecessors to patch panels and were commonly used to support low-bandwidth Ethernet and token-ring networks. The most common punch blocks are the 66 and 110 blocks. They are used to connect station cabling to the trunk cabling that goes from an IDF to the MDF. The 66 block has been widely used for splicing 25 pairs of telephone wires together. 110 blocks connect a punched down wire on one side to pre-connected patch cables with connectors such as RJ-45 or Telco 50-pin on the other side.
A 66 block is a type of punch down block used to connect sets of wires in a telephone system. They have been manufactured in three sizes, A, B and M. A and B have six clips in each row while M has only 4. Each row of a 66 block is set up for one pair of wires to be spliced to another pair. however, any pair of clips can be used to connect any two wires.
The A blocks spaced the rows further apart, and has been obsolete for many years. The B style is used mainly in distribution panels where several destinations (often 1A2 key telephones) need to connect to the same source. The M blocks are often used to connect a single instrument to such a distribution block. 66 blocks are designed to terminate 22 through 26 AWG solid copper wire. 66 blocks are available pre-assembled with an RJ-21 female connector that accepts a quick connection to a 25-pair cable with a male end. These connections are typically made between the block and the customer premises equipment (CPE).
A 110 blocks is a updated version of punch down block, is the core part of the connection management system, used to connect wiring for telephone systems, data network wiring, and other low-voltage wiring applications. 110 type wiring block is flame retardant, injection-molded plastic to do the basic devices and the termination cabling system is connecting on it.
The 110 block is designed for 22 through 26 gauge solid wire. This is the termination used on cat5e patch panel, cat 6 patch panel and RJ-45 jacks. They are also formed into block type terminations the size of small 66 blocks. The 110 block is designed for 500 MHz (1 gb/s) or greater bandwidth. 110 blocks are acceptable for use with AES/EBU digital audio at sample rates greater than 268 KHz as well as gigabit networks and analog audio.
The specifications of 110 Wiring Blocks are as follows: 25 pairs 110 type wiring block, 50 pairs 110 type wiring block, 110 pairs 110 type wiring block, 300 pairs 110 type wiring block. The distribution frame package of 110 type wiring blocks should also include 4 or 5 blocks, connection block, blank labels and tags folder and the base. 110 type wiring block system uses easy quick-fit plug-hop loops which can be simply rearranged, so it provides a convenient cross-connect to non-professional and technical personnel management system.
Punch down tool is used to force solid wire into metal slots on the block. Present residences typically have phone lines entering the house to a sole 66 or 110 block, and then it is spread by on-premises wiring to outlet boxes all over the house in a star topology.
Both styles of punch block use a punch down tool to terminate the wires to the block. To terminate a wire, you place it into the terminal and then push it down to make contact with the punch down tool. The punch down tool fits around a 66 block terminal or into a 110 block terminal. One side of the blade is sharp to cut the wire off flush, this is normally marked on the tool with the word cut. Be sure to have this side oriented to cut off the loose end of the wire and not the end going to the other block. Hide extra cable behind the block in case you ever have to re-terminate a pair so that you don’t have to re-terminate the entire cable.
Whatever the dimensions of the punch down tools are, usage is the same. Many tools have a dual blade that can be flipped depending on which style of block is in use.