Insulation-displacement connector
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Insulation-displacement connectors and the related Insulation-piercing connectors are designed to be connected to the conductor of an insulated wire by a connection process which forces a blade or blades through the insulation, removing the need to strip the wire before connecting. Such connections are usually seen in low current applications such as telecoms, networking and signal connections between parts of an electronic or computer system. When properly made, the connector blade cold-welds to the wire, making a highly reliable gas-tight connection.[1][2]
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[edit] Ribbon cable
Ribbon cable (a.k.a. multi-wire planar cable) is designed to be used with multi-way IDC connectors in such a way that many IDC connections can be made at once, saving time in applications where many connections are needed. These connectors are not designed to be reusable, but can often be re-used if care is taken when removing the cable.
Pin 1 is typically indicated on the body of the connector by a red or raised 'V' mark
[edit] Telephone and network plugs
In some types of telephone and network plug including the BS 6312 and the registered jack family, generally separate wires in a sheath are used. In these applications, the outer sheath is stripped then the wires are inserted into the connector and a special crimp tool is used to force the contacts into the wires. Traditionally these connectors have been used with flat cable which makes it easy to ensure the right wires go into the right slots. However modular connectors generally used with Category 5 twisted pair cable requires careful arranging of the wires by hand before inserting them into the connector.
[edit] Punchdown blocks
Punchdown blocks are intended to take individual wires punched down into each position in the block with a special tool. The exact size of the tool varies by brand which can cause problems for those working on existing installations. It is usually possible to insert wiring without the proper tools though this requires care to avoid damaging the connectors (e.g. pushing a screwdriver down the middle of the block is bad practice as it forces the two blades of the connector apart leading to bad contacts). They are generally seen in telephone and network wall sockets, in patch panels and distribution frames, and in telephone equipment like PBXs. It is usually possible to put multiple wires in one way of a punchdown block though if they are of different thicknessess this can cause contact problems for the thinner wire.
[edit] Common layouts
Connectors are categorized by pin spacing in mm (pitch), number of pins, and number of rows. Common connectors are:
[edit] Computing
- 3.5" IDE desktop computer hard disc drives - 2.54mm pitch, 40 pins, 2x20 (2 rows of 20 pins)
- 2.5" IDE notebook computer hard disc drives - 2.00mm pitch, 44 pins, 2x22 (2 rows of 22 pins)
- Serial DB-9 on Motherboards - 2.54mm pitch, 10 pins, 2x5 (2 rows of 5 pins) - AKA "everex"
- Serial DB-25 on Motherboards
[edit] See also
- Vampire tap, another insulation-piercing connector
- Wire wrap
[edit] Notes
- ^ Basics of Design Engineering http://www.machinedesign.com/BDE/Electrical/bdeee10/bdeee10_3.html#insulate
- ^ "Insulation Displacing Connector Technology". Molex. http://www.molex.com/tnotes/idtbm.html. Retrieved 2007-04-15.
[edit] References
- IDC Cable, Headers & Connectors
- Brochure on 3M Scotchlok insulation displacement connectors
- Molex Connectors Explained, as used in Pinball
- Insulation Displacement Contact Technology from Sensors, May 2001.
- A New Type of Very High Reliability Torsion IDC Zierick Manufacturing Corporation white paper.
- AT/Everex wiring for RS-232 COM port
