Punch Down Block - Reliable Connections

Reliable Connections

It is possible to insert wiring without the proper tool, but this requires great care to avoid damaging the connectors. For example, pushing a screwdriver down the middle of the block is a bad practice as it forces the two blades of the terminal post apart, leading to bad contacts. It is also possible to punch down multiple wires on top of each other in a single post of a punch down block, but this practice is discouraged because of reliability concerns. If these multiple wires are of different thicknesses (wire gauges), it is even more likely that the thinner wire will develop contact problems. Similarly, stranded wire can be used on punch down blocks, even though they were originally designed for solid wire connections.

Marginal practices like these are strongly discouraged in large or mission-critical installations, because they can introduce extremely troublesome intermittent connections, as well as more-obvious outright bad connections. Once the contact blades in a punchdown block are "sprung apart" by poor practices, the entire block often must be replaced to restore reliable connections.

In addition, punch down blocks are being used to handle larger numbers of faster data signals, requiring greater care and proper procedures to control impedance and crosstalk.