“U” channel sections of fiberglass cloth reinforced with epoxy used to protect wire and cable.

A technique to dynamically measure the diameter of a coated wire or cable as it is being produced on line. There are a number of technologies available to accomplish this task, but they can be classified as either non-contact or contact. This measuring instrument, usually found on an extruder, enables the operator or the automatic machine controls to adjust either the line speed or the extruder output screw speed to apply the proper amount of insulation over the bare conductor. Various types are available and are grouped into two categories: contact and non-contact.

Past contact methods once used feeler gauges that would contact the cable product to measure the size, with those readings used to manually control the extruder settings. Newer methods include the use of two synthetic sapphires at a low contact pressure, with the readings used to automatically make adjustments to the cable size by adjusting the cable or extruder speed.

Since the 1980s, non-contact diameter gauges have become increasingly important, with a form of light (typically lasers) the key. This technology can be used to automatically control cable size. There are different types of systems that use lasers. A laser-scanning system typically uses a laser beam directed at an inspection area that strikes a rotating multi-sided mirror that creates from 80 to 200 scans per second. Those scans are received by a photoelectric cell based on the relative time intervals of light and shadow as the light beam is interrupted periodically by the cable. It has a frequency of approximately 6 Hz. A laser-diffraction analysis system, a more sophisticated optical technology, can measure cable 500 times per second, with the results analyzed by laser diffraction analysis. Another non-contact system uses the same CCD technology used in video cameras. The “camera” monitors the cable as it passes by. The control system measures the number of pixels that are occupied by the cable image and translates it into a dimension. All three systems can employ closed-loop control of the extrusion process.

An electronically operated device for continuously indicating the degree of eccentricity of the conductor relative to the surrounding dielectric in extruded wires and cables. A non-destructive test used to control production and for inspection on the final product.

The four most important characteristics in an electronic cable are impedance, attenuation, shielding and capacitance. See individual listings.

A cable draped in accordion fashion from sliding or rolling hangers, usually used to feed moving equipment such as bridge cranes.

The material used in multiple-conductor cables to occupy the interstices formed by the assembly of the insulated conductors, thus forming a cable core of the desired shape (usually circular).

Rectangular pieces of fiberglass laminated epoxy (155°C) used to protect delicate cable harness and connectors.

See Sheath.

A tool for pulling through a conduit. Also, firms that fabricate cable assemblies by pulling the conductors through a plastic, rubber or neoprene tube.

The vertical or horizontal open support (usually made of aluminum or steel) that is attached to a ceiling or wall.

See Vertical Riser.

The outermost covering of a cable providing overall protection.

Used in the aerial suspension of communication and power cables to bind the cable into close contact with the supporting wire.

A room adjacent to a control room to facilitate routing of cables in trays away from the control panels.

A device that seals the end of a cable and provides insulated egress for the conductors. In power work, also known as a “pothead” or “end bell.”

A range of tests that are used to evaluate the characteristic of a cable to standards from bodies such as the National Bureau of Standards and ASTM.

Belt-like plastic strip device that loops around bundles of cables or insulated wires to hold them together (and sometimes to anchor them to an electronic cabinet, a wall or another assembly).

A rigid structural system used to support cables and raceways. Types of cable trays include ladder, ventilated trough, ventilated channel and solid bottom. Often used for telecommunications.