Dimensions are shown in mm (inch)
Dimensions subject to change
D Subminiature Glossary of Terms
Glossary of Terms
In every job speciality there are certain words and
phrases used by the ‘‘insiders’’ which after a time
become almost a language unique to that
speciality. D Subminiature technology is a typical
example of that condition.
The following pages provide some explanations, in
an attempt to clarify some of the terms that are
commonly used by engineers and sales staff at ITT
Cannon.
The list is not comprehensive, but highlights many
of the expressions commonly used. Should you
have any comments or additions please contact
us. Feedback will be appreciated.
Accelerated Aging — A connector test in which
temperature, voltage, current, or other parameters
are increased beyond the normal operating values
to observe deterioration in a relatively short period
of time.
Accessories — Auxiliary devices such as cable
clamps, endbells, gaskets, or any number of
mechanical hardware devices that can be added to
a connector.
Alloy — A composition of two or more elements,
of which at least one is a metal. In connector
applications it is usually a combination of metals
which is used to create an alloy superior in
performance to any of its individual components.
Alternating Current — A flow of electricity which
reaches a maximum in one direction, decreases to
zero, then reverses itself and reaches maximum in
the opposite direction. This cycle is repeated
continuously. The number of such cycles per
second is the frequency. The average value of the
voltage during any cycle is zero. Abbreviated ac.
Ambient Temperature — The temperature of the
environment surrounding the connector. Usually
the air. Normally used as the reference when
specifying the OPERATING TEMPERATURE range
of the connector.
Ampere — A unit of electrical current or rate of
flow of electrons. One volt across one ohm of
resistance causes a current of 1 ampere.
Abbreviated Amp or A.
Anodize — A protective, insulating oxide layer
formed on a metal by electrolytic action.
Occasionally used as the outer most layer in
connector plating, anodize is a very tough, non-
conductive plating.
Attenuation — Power loss in an electrical system,
expressed in decibels.
AWG — American Wire Gauge. A standard for wire
diameters based on the approximate circular mil
area of the wire. As numbers get larger, wire
diameters decrease in size (a size 16 AWG wire
has a larger diameter than a size 22 AWG).
Backshell — (Also known as Endbell) The outer
rear end of the connector which is attached by
means of internal threads or screws. It adapts the
connector to its wire connections in a variety of
ways. Typical backshells might have cable clamps
to secure a wire bundle, ridges for heat shrink
tubing, pipe threads, or shielded termination
mechanisms. Backshells may be straight, 90°, or
45°.
Bandwidth — The range of frequencies within
which performance falls within specific limits.
Usually the bandwidth is given as an operating
range and the operating specifications apply only
to that bandwidth, unless otherwise stated.
Bar — A centimeter-gram-second unit of pressure
(force exerted on a unit of area) equal to 1,000,000
dynes per square centimeter. Formerly known as
microbar. Its symbol is b.
Base Metal — The metal which the connector or
connector component is made and over which
various platings will be deposited.
Beryllium Copper — An alloy of copper used to
make contacts. It is relatively expensive, but has
superior spring qualities, is resistant to fatigue, and
can operate at higher temperatures than other
materials such as phosphor bronze. It is used
when numerous insertion and extraction cycles
are required.
Body — The main portion of the connector made
of the shell, insulator, and contacts.
Boot — A rear accessory, usually made of a
resilient material, which is used around a
multiconductor cable to add additional insulation,
strength, abrasion resistance, or sealing.
Brass — Metal alloy of copper and zinc used for
contacts. It is low cost, an excellent conductor,
and resists fatigue.
Breakdown — An electrical discharge through a
connector insulator or insulation on a wire. A
catastrophic failure mode.
Breakdown Voltage — The voltage at which an
insulator ruptures.
Breakout — The point at which wires are
separated from a multi-conductor cable or wire
bundle for routing to other points.
C — Abbreviation for Centigrade, or more properly
Celsius, since the term Centigrade was officially
abandoned by international agreement in 1948.
See CELSIUS.
Cable Assembly — A cable (or bundle of cables)
with plugs and/or receptacles on each end.
Cable Clamp — A rear connector clamping
accessory which tightens over a cable or wire
bundle to provide strain relief to the cable. The
cable clamp may be part of a more elaborate
endbell or it may be used alone. Some cable
clamps also provide cable jacket sealing using a
resilient gland; for example the MS3057-C, others
provide only strain relief.
Cadmium — A metallic element chemically
related to zinc and mercury, widely used for
plating. It has an extraordinary ability to resist
outdoor corrosion. It is especially resistant to
alkali. Cadmium is electrically conductive and it is
easy to solder. Its symbol is Cd.
CECC — Abbreviation for Electronic Components
Committee of CENELEC, the European committee
for Electrotechnical Standardization. CECC uses
the IEC test methods, and thus is based upon
worldwide standards.
Celsius — A temperature scale in which the
freezing point of water is 0° and the boiling point is
100° at normal atmospheric pressure. Formerly
known as Centigrade, but officially changed to
Celsius by international agreement in 1948.
CEN — Abbreviation for European Committee for
Standardization. A European standards group
corresponding to the ISO at the European level.
CENELEC — Abbreviation for European
Committee for Electrical Standardization. A
European standards group corresponding to the
IEC at the European level.
Chamfer — A bevel cut on the inside edge of an
insulator contact cavity or a mounting hole. In a
contact cavity the chamfer is intended to guide the
mating pin into the cavity. In a mounting hole it is a
countersink to accept a cone shaped bolt.
Characteristic Impedance — The characteristic
impedance of a transmission line is the impedance
of the line when it is terminated in a perfect load (a
load that absorbs all the energy and reflects none,
such that VSWR = 1.00).
Clearance Hole — See Through Hole.
Closed Entry — An insulator design which limits
the diameter of the mating contacts.
R e a d e r ’ s R e s o u r c e
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