S
A UL cable type. Hard service flexible cord with thermoset insulation and jacket

SAE
Society of Automotive Engineers

S Band
A band of frequencies between 1,550 and 5,200 megahertz

SBR
A copolymer of styrene and butadiene. Also GRS or Buna-S

Schering Bridge
See Bridge

SDN
A small diameter multiconductor control cable with neoprene jacket and nylon sheath over polyethylene insulation

Secondary Insulation
A nonconductive material that protects the conductor against abrasion and provides a second barrier

Segmental Conductor
A stranded conductor consisting of three or more stranded conducting elements, each element having approximately the shape of the sector of a circle, assembled to give a substantially circular cross-section

Self-Extinguishing
Characteristic of a material whose flame is extinguished after the igniting flame source is removed

Semiconductor
In wire industry terminology, a material possessing electrical conduction properties that fall somewhere between conductors and insulators. Usually made by adding carbon particles to an insulator. Not the same as semiconductor materials such as silicon, germanium etc., used for making transistors and diodes

Semiconducting jacket
A jacket having a sufficiently low resistance so that its outer surface can be kept at substantially ground potential

Semirigid Cable
Generally refers to Type MI or Type ALS which can be bent or shaped into a required configiration from coils or reels

Semirigid PVC
A hard semiflexible polyvinylchloride compund with low plasticizer content

Semisolid
An insulation cross-section having a partially open space between the conductor and the insulation perimeter

Sensitive Conductor
A conductor terminated to a circuit that is adversely affected by spurious signals

Separable Insulated Connector
A insulated device to facilitate cable connections and separations

Separator
Pertaining to wire and cable, a layer of insulating material such as textile, paper, Mylar etc., which is placed between a conductor and its dielectric, between a cable jacket and the components it covers, or between various components of a multiple conductor cable. It can be utilized to improve stripping qualities and/or flexibility, or can offer additional mechanical or electrical protection to the components it separates

Serial Interface
An interface which requires serial transmission, or the transfer of information in which the bits composing a character are sent sequentially. Implies only a single transmission channel

Series Circuit
A circuit in which the components are arranged end to end to form a single path for current

Serve
A filament or group of filaments such as fibers or wires, wound around a central core

Served Wire Armor
Spiral wrap of soft galvanized steel wires wrapped around a cable to afford mechanical protection and increase the cable-pulling tension characteristic

Serving
A wrapping applied over the core of a cable or over a wire

SEU
A UL cable type. Service Entrance Undergound Cable, 600 volts

SEW, SEWF
A CSA cable type. Silicone rubber-insulated equipment wire

SF
A CSA cable type. Silicone rubber insulated fixture wire, solid or 7 strand conductor, 200ºC

SFF
A CSA cable type. Same as SF, except flexible stranding 150ºC

SG
A CSA cable type. Same as SW except with ground wires

SGO
A CSA cable type. Same as SWO except with ground wires

SHD
Portable mine power cable, three or four individually shielded conductors, with grounding conductors, 5 through 25 kV

Sheath
The outer covering or jacket over the insulated conductors to provide mechanical protection for the conductors

Shield
A sheet, screen, or braid of metal, usually copper, aluminum, or other conducting material placed around or between electric circuits or cables or their components, to contain any unwanted radiation, or to kee out any unwanted intereference

Shield Coverage
See Shield Percentage

Shielded Insulated Splice
An insulated splice in which a conducting material is employed over the full length of the insulation for electric stress control

Shielded Line
A transmission line whose elements confine radio waves to an essentially finite space inside a tubular conducting surface called the sheath, thus preventing the line from radiating radio waves

Shield Effectiveness
The relative ability of a shield to screen out undesirable radiation. Frequently confused with the term shield percentage. Which it is not

Shielding, Power Cable
A conducting layer, applied to control the dielectric stresses within tolerable limits and minimize voids

Short
A low resistance path that results in excessive current flow and often in damage

Shovel Cable
Normally an SHD-GC type which supplies high-voltage (2 to 25 kV) power to mobile equipment

Shrinking Ratio
The ratio between the expanded diameter and recovered diameter of shrinkable products

Shrink Temperature
That temperature which affects complete recovery of a heat shrinkable product from the expanded state

Shrink Tubing
Tubing which has been extruded, cross-linked, and mechanically expanded which when reheated or released will return to its original diameter

Shunt
A very low resistance component used to divert a portion of the current

SI
An international system of standardized units of measurement

SIC (Specific Inductive Capacitance)
See Dielectric Constant

Signal
Any visible or audio indication whch can convey information. Also, the information conveyed through a communication system

Signal Cable
A cable designed to carry current of usually less than one ampere per conductor

Signal-to-Noise Ratio
A ratio of the amplitude in a desired signal to the amplitude of noise, usually expressed in db

Silicone
A material made from silicon and oxygen. Can be in thermosetting elastomer or liquid form. The thermosetting elastomer form is noted for high heat resistance

Single Cable
A one-cable system in broadband LANs in which a portion of the bandwidth is allocated for send signals, and a porion for receive signals, with a guard band in between to provide isolation from interference

Single Mode
Optical fiber in which only one mode of light can propogate

Sintering
Fusion of a spirally applied tape wrap insulation or jacket by the use of gigh heat to a homogenous continuum. Usually employed for fluorocarbon, non extrudable materials

SIS
Switchboard wiring made with cross-linked polyethylene insulation

SJ
A UL cable type. Junior hard service, rubber-insulated pendant or portable cord. Same construction as Type S, but 300V

SJO
Same as SJ but with oil-resistant jacket

SJOO
Same as SJO, but with oil-resistant insulation as well as oil-resistant jacket

SJT
A UL cable type. Junior hard service thermoplastic or rubber insulated conductors with overall thermoplastic jacket, 300V

SJTO
Same as SJT but with oil-resistant outer jacket

SJTOO
Same as SJTO but with oil-resistant insulation

Skin Effect
The tendency of alternating current as its frequency increases, to travel only on the surface of a conductor

S Meter
An instrument to measure signal strength

S/N
See Signal-to-Noise Radio

SNM
Shielded Nonmetallic sheathed cable

SO
A UL cable type. Hard service cord, same construction as Type S except oil-thermoset jacket, 600V

Soft Wire
Wire that has been drawn or rolled to final size and then heated (annealed) to remove the effects of cold working

Solid Conductor
A conductor consisting of a single wire

SOO
Same as So but with oi-resistant insulation

SOOW-A
A UL cable type. Portable cord and control cable. 600V. Same as SOO but UL Listed for outdoor use

Source Coupling Loss
Loss of light intensity as the light from a source passes into an optical fiber

SOW
A CSA cable type. A water-resistant thermoset-jacketed portable cord approved for outdoor use

Spacer Cable
A type of overhead power distribution cable. Spacing is accomplished by ceramic or plastic hangers suspended from a support messenger

Span
In flat conductors, distance between the reference edge of the first and the last conductor. In round conductors, distance between centers of the first and last conductors

SPC
Statistical Process Control

Specific Inductive Capacity (SIC)
Dielectric constant of insulating material

Spiral Shield
A metallic shield of fine stranded wires applied spirally rather than braided

Spiral Stripe
A color coding stripe applied helically to the surface of an insulated wire or cable

Spiral Wrap
The helical wrap of a tape or thread over a core

Splice
A connection of two or more conductors or cables to provide good mechanical strength as well as good electrical conductivity

Splitter
A passive device used in a cable system to divide the power of a single input into two or more outputs of lesser power. Can also be used as a combiner when two or more inputs are combined into a single output

SP-1
A UL cable type. All thermoset, parallel-jacketed, two-conductor light duty cord for pendant or portable use in damp locations, 300V

SP-2
Same as SP-1, but heavier construction, with or without third conductor for grounding purposes, 300V

SP-3
Same as SP-2, but heavier construction for refrigerators or room air-conditioners, 300V

SPR
A UL type of thermoplastic-insulated, 2 or 3 conductor parallel cord. Frequently called "Zip cord" or "Lamp Cord"

Squirrel Cage Motor
An induction motor having the primary winding (usually the stator) connected to the power and a current is induced in the secondary cage winding (usually the rotor)

SR
Silicone rubber cable, 600|V 125ºC

SR-AW
A cable with flexible, nickel-plated copper conductor, silicone rubber insulation, glass braid, 600V 200ºC

SR-C
A cable with solid copper conductor, silicone rubber insulation, glass braid, 600V 125ºC

SRG
A cable with ozone resistant silicone rubber insulation with an overall jacket of braided glass yarn impregnated with flame, heat and moisture resistant finish. 150/200ºC, 600V appliance and motor lead wire

SRGK
A cable with ozone resistant silicone rubber insulation with braided glass yarn conductor jacket. Cable core of insulated conductors shielded or unshielded, and an overall jacket of braided K-fiber impregnated with flame, heat and moisture resistant finish. 150/200ºC, 600V multiconductor cable

SRK
A UL cable type. Hard service cord, jacketed, same as type S except thermoplastic construction. 600V, 60ºC to 105ºC

Stability Factor
The difference between the percentage power factor at 80 volts/mil and at 40 volts/mil measured on wire immersed in water at 75ºC for a specified time

Standard
A set of ruled or protocols that describe how a device should be manufacured so it will be reliable and interoperability (compatibility) with others of the same type from different manufacturers will be maintained

Standing Wave
The stationary pattern of waves produced by two waves of the same frequency travelling in opposite directions on the same transmission line. The existence of voltage and current maxima and minima along a transmission line is a result of reflected energy from an impedance mismatch

Standing Wave Ratio
In a transmission line, waveguide, or analogous system, a figure of merit is used to express the efficiency of the system in transmitting power

Standing Wave Ratio (SWR)
A ratio of the maximum amplitude of a standing wave in current or voltage amplitudes

Static Charge
A electrical charge that is bound to an object. An unmoving electrical charge

Stay Cord
A component of a cable, usually a high-tensile textile, used to anchor the cable ends at their points of terminationand to keep any pull on the cable being transferred to the electrical connections

Step Index Fiber
A multimode optical fiber consisting of a core of uniform refractive index, surrounded by cladding of slightly lower refractive index

Stiffness
As applied to copper, the property of a conductor that causes it to resist permanent deformation by bending

STO
Same as ST but with oil-resistant thermoplastic outer jacket, 600V 60ºC

STOO
Same as STO but with oil-resistant insulation

Stop Joint
A splice which is designed to prevent any transfer of dielectric fluid between the cables being joined

STP
Shielded Twisted Pair. Two wires, wound around each other to help cancel out any induced noise in balanced circuits. Multiple pairs of wires are contained in one sheath, and each wire pair is shielded

Straight Joint
A cable splice used for connecting two lengths of cable, each of which consists of one or more conductors

Strain Gauge
A device for determining the amount of strain (change in dimension) when a stress is applied

Strain Hardening
An increase in hardness and strength caused by plastic deformation at temperatures lower thena the recrystallization range

Strand
One of the wires of any stranded conductor

Stranded Conductor
A conductor composed of a group of wires, usually twisted, or of any combination of such groups of wires

Strand Lay
The distance of advance of one strand of a spirally stranded conductor, in one turn, measured longitudinally

Stress-Relief Cable
Cable used to relieve stresses in the process of welding pipe joints by inducing heat in pipe sections to be welded, flexible copper strand

Stress-Relief Cone (Termination)
A device used to relieve the electrical stress at a shielded cable termination; genereally used at 5 kV and above

Strip
To remove insulation from a wire or cable

Structural Return Loss
Backward reflected energies from uneven parts of the cable structure

Subchannel
A frequency subdivision created from the capacity of on pyhsical channel by broadband LAN technology. Bands of frequencies of the same or different sizes are assigned to transmission of voice, data, or video signals. Actual transmission paths are created when each assigned band is divided, using FDM, into a number of subchannels

Subsplit
The most common form of transmission in the CATV industry. In the sub-split scheme, the bandwidth utilized to send toward the head-end (reverse direction) is much smaller, from approximately 5 MHz to 30 MHz, and the bandwidth utilized to transmit from the head-end (forward direction) is very large from approximately 55 MHz to 300 MHz. The guard band between forward and reverse directions (30 MHz to 55 MHz) provides isolation from interference

Substrate
Insulating material of a printed circuit

Suggested Working Voltage
AC voltage that can be applied between adjacent conductors

Superconductors
Materials whose resistance and magnetic permeability are virtually zero at very low temperatures

Suppressor
A device used to reduce or eliminate unwanted voltages in electric or electronic circuits. For example, a resistance conductor in, or a resistor series with, a sparkplug cable, to suppress interference which would otherwise affect radio reception in and near the vehicle

Surface Resistivity
The resistance of a material between two opposite sides of a unit square of its surface. It is usually expressed in ohms

Surge
A temporary and relatively large increase in the voltage or current in an electric circuit or cable. Also called transient

SV
A UL cable type. Vacuum cleaner cord, two or three conductor, rubber insulated. Overall rubber jacket. For light duty in damp locations, 300V 60ºC

SVO
A UL cable type. Same as SV except oil-resistant thermoset jacket. 300V 60ºC or 90ºC

SVT
A UL cable type. Same as SV except thermoplastic jacket. 300V 60ºC or 90ºC

SVTO
A UL cable type. Same as SVT, except with oil-resistant thermoplastic jacket, 60ºC

SW
A CSA cable type. Rubber jacketed power supply cable (8 AWG to 2 AWG) 600V

Sweep Test
A test given to check attenuation by an oscilloscope, as in coaxial cable

SWO
Same as SW except neoprene jacketed

SWT
A CSA cable type. Plastic-jacketed power supply cable (8 AWG to 2 AWG) 600V