Fiber Optic Center Glossary
View: Glossary, Acronyms, Military Specifications for Connectors
There are currently 109 names in this directory beginning with the letter H.
Halar
A trade name of Allied Chemical for their copolymer of ethylene and chlorotrifluor-ethylene. Abbreviation ECTFE.
Half Duplex
A telecommunications device allowing two-way transmission of signals or other information, but only in one direction at a time. Thus a half-duplex device cannot simultaneously transmit and receive, though interspersed bursts in each direction are possible.
Half Duplex Transmission
1) Data transmission over a circuit capable of transmitting in either direction, but only one direction at a time. 2) Mode of operation between two communications devices where only one of them can send or receive at a time.
Halogen
A term used to identify any of the four elements chlorine, fluorine, bromine and iodine, grouped together because their chemical properties are similar.
Halogen Rating
Identifies if a thermoplatic polymer, elastomer, or thermoset rubber has or contains halogen elements. Halogen is an electro-negative atomic element which, if combined with a metal, forms a haloid salt. Halogens are chloride, fluorine, bromine, iodine and astatine. Halogen containing compounds, if exposed to flame, produce corrosive and potentially toxic fumes. Materials can be identified as either halogen-gree or as halogenated.
Halogen-Free
A designation for gases produced during flame and burning of materials or cables. Halogen-free materials do not release potentially toxic chlorine or fluorine gasses. Toxicity of gases under flame and burning conditions is a factor in persons' survivability. There is a test methodology for toxicity which is CTI and the test method is UTE C 20.
Handhole
An access opening provided in equipment or in a below-the-surface enclosure into which personnel reach, but do not enter, to work with or place cable. Also known as maintenance access handhole.
Handoff
Cellular systems are designed so that a phone call can be initiated while driving in one cell and continued as more cells are driven through. The transfer to a new cell is called the handoff and is designed to be transparent to the cellular phone user. This handoff is achieved by network computers which assign the call to another tower just as the user passes from one cell to another, ensuring continuous service.
Handshaking
Exchange of predetermined signals when a connection is established between two data set devices.
Hard Clad Silica (Fiber Optic)
Abbreviated HCS, it is a structure in fibers where the cladding around the glass core is a hard plastic, as opposed to a "PCS," which is a soft plastic cladding.
Hard Conversion
The process of changing a measurement from inch-pound units to nonequivalent metric units that necessitates physical configuration changes outside those permitted by established measurement tolerances. See Soft Conversion
Hard Cure, AL-33xx Series
ÅngströmLink® hard materials with Shore D durometer. All are suited to making thin films for use in PCB optical waveguides, microlens arrays, prism films, or low dielectric layers. Can be applied by spin coating. Compatible with CMOS substrates and fabrication techniques. Excellent adhesion and chemical resistance.
Hardener
A substance or mixture of substances added to an adhesive to promote or control the curing reaction by taking part in it. The term is also used to designate a substance added to control the degree of hardness of the cured fill. Same as curing agent. See also catalyst.
Hardness
A general term that correlates with strength, rigidity and resistance to abrasion or penetration. Measured on Shoer or Rockwell scales.
Harmonica
A cable adapter used to change an Amphenol type 50 pin Telco connector into multiple RJ-45’s or RJ-11’s.
Harmonized Code
An international coding system for specifying the attributes of cord voltages, jackets, diameters, etc.
Harness
1)An arrangement of wires and cables, usually with many breakouts, which have been tied together or pulled into a rubber or plastic sheath, used to interconnect electric circuits. 2)A group of wires or cables routed together with attached connectors and components, secured to provide a pre-shaped electrical wire or cable assembly.
Harness , Outdoor use
(Also Cable) Outdoor Use Cables/Harnesses: Product expected to withstand exposure to he elements of weather.
Harnessing Devices
Tying tapes, lacing cords, and flexible sleevings which are used for wire and cable bundling, harnessing, and holding. Other devices include plastic ties or clamps, spiral-cut plastic tubing, and plastic U-shaped trays or ducts.
Hazardous Location
Ignitable vapors, dust, or fibers that may cause fire or explosion as defined by the NEC.
Head Assembly
A positioner designed to attach to a crimping tool in place of a turret head. (MIL-STD)
Headend
The point in a LAN where the inbound signals are transferred into outbound signals. The headend may be passive or contain an amplifier or frequency translation equipment. Used in broadband LANs and CATV.
Heat Activated Adhesive
A type of adhesive pre-applied to one or both adherends, that is rendered tacky by application of heat and forms a bond on cooling.
Heat Endurance
The time of heat aging that a material can withstand before failing a specific physical or electrical test.
Heat Shock
Test to determine the stability of a material when exposed to a sudden high temperature change for a short period of time.
Heat Treating
A process that uses precise heating and tooling of metals after stamping and forming in order to optimize internal stresses and spring properties.
Heater Cord
Flexible stranded copper conductor, cotton wrapped with rubber insulation and asbestos roving .
Heel Bead
The ability of a tape to with_stand exposure to specified temperatures after applica_tion to a surface. Clean removal after exposure may or may not be important depending on the intended func_tion of the tape and the type of adhesive.
Helical Stripe
A continuous, colored, spiral stripe applied over the outer perimeter of an insulated conductor for circuit identification purposes.
Henry (H)
The standard unit of inductance. The inductance of a current is a one Henry when a current variation of one ampere per second induces one volt.
Hermaphroditic Connector
A connector design which utilized pin and socket contacts in a balanced arrangement such that both mating connectors are identical. The contacts may also be hermaphroditic and may be arranged as male and female contacts as for pins and sockets. Hermaphroditic contacts may also be used in a manner such that one half of each contact mating surface protrudes beyond the connector interface and both mating connectors are identical (MIL-STD)
Hermaphroditic Contact
A contact design which is a combination pin and socket and which mates with other contacts of the same design. (MIL-STD) Both mating elements are precisely alike at their mating face
Hermetic
Permanently sealed by fusion, soldering, or other means to prevent the transmission of air, moisture vapor, and all other gases. Hermeticity is usually expressed as the rate of leakage volume of tracer gas (such as helium) per second in time.
Hermetic Seal
Connector contacts are bonded to the connector by glass or other materials which permit maximum leakage rate of gas through the connector of 1.0 micron ft./hr. at one atmosphere pressure for special applications.
Hermetically Sealed
A gas-tight enclosure that has been completely sealed by fusion or other comparable means.
Hertz
Unit of measure of frequency of alternating current. One hertz is equal to one cycle per second.
Heterogeneous Insulation
A cable insulating system composed of two or more layers of different insulating materials.
Hi-pot
A test designed to determine the highest potential that can be applied to a conductor without breaking through the insulation.
High definition television (HDTV)
Digital television with significantly more resolution than that provided by a good NTSC or PAL television signal. The specific resolution can vary, however it is typically about twice the resolution of standard television signals, and has a wider aspect ratio.
High Frequency (HF)
The band from 3 MHz to 30 MHz in the radio spectrum, as designated by the Federal Communications Commission.
High performance parallel interface (HIPPI)
A system for high-speed supercomputer-to-supercomputer connectivity above 1 Gb/s.
High Strength Alloy Conductor
A conductor which shows a maximum 20% increase in resistance and a minimum of a 70% increase in breaking strength over the equivalent construction in pure copper while exhibiting a minimum elongation of 5% in 10 inches.
High temperature crossover (TxOver)
Temperature at which an adhesive loses its elastomeric properties and melts to a flowable liquid. This value is a stability indicator for high temperature applications. For example, the higher the value, generally, the more heat stable the product is.
High Temperature Wire and Cable
Electrical wire and cables having thermal operating characteristics of 150°C and higher.
High Voltage (HV)
Cables rated over 35Kv. The National Electrical Code defines any cable over 600 volts as High Voltage for the purposes of Article 710. However, Article 326 delineates the generally accepted parameters of Medium Voltage and High Voltage .
High wire resistance
The expected connection is established but the current is weak due to current being limited as it runs through the connection.
High-density connector
Typically, connectors with multiple fibers in a small form factorhousing, i.e., MPO/MTP, MT-RJ.
High-density polyethylene (HDPE)
A jacketing material used in harsh environments to protect cables from accidental chemical exposure.
High-Lever Data Link Control (HDLC)
The protocol defined by ISO in 1976 for bit-oriented, frame-delimited data communications
high-speed unwind
The unwinding or dispensing of tapes at a relatively high rate of speed, usually over 50 feet per minute.
Higher Performance Radio Local-Area Network (HIPERLAN)
HIPERLAN is the European standard for short-range (approx. 50m) high performance radio local-area networks. HIPERLAN operates in the 5.1-to-5.3-GHz band. Another band may be available in the future operating in the 17.1-to-17.3-GHz range, but as of 8/97, specifications have not been finalized.
Holiday
A small defect, particularly in an electrical or pipe wrapping tape, which lowers the dielectric strength at the point of the defect below a certain desired minimum.
Home Location Register
The data base of customer information that makes subscriber information available to a mobile-telephone switching office. The register functions as a network element.
Home Run
A PON architecture where the optical splitter is housed at the service provider’s facility. Home runs are the easiest for handling changes, but require a fiber rich cabling system as one fiber is dedicated for each subscriber. A cable run going from a workstation or office directly back to a wiring closet with no other connections. Physical star topologies consist exclusively of home runs.
Homogeneous Insulation
A complete cable insulation structure whose components cannot be identified as layers of different materials.
Homopolymer
a polymer derived from one species of (real, implicit, or hypothetical) monomer. Note many polymers are made by mutual reaction of complementary monomers. These monomers can readily be visualized as reacting to give an "implicit monomer", the homopolymerization of which would give the actual product, which can then be regarded as a homopolymer. Example poly(ethylene terephthalate). Some polymers are obtained by modification of other polymers such that the structure of the macromolecules that constitute the resulting polymer can be thought of as having been formed by homopolymerization of a "hypothetical monomer". These polymers can be regarded as homopolymers. Example poly(vinyl alcohol). (IUPAC)
Hood
An enclosure attached to the back of a connector to contain and protect the wires and cable attached to the terminals of a connector.See also Backshell.
Hook-up Wire
Single conductor used to hook-up electrical parts of instruments for low current and voltage (under 1000 volts).
Horizontal Cabling
The wiring/cabling between the telecommunications outlet/connector and the horizontal cross-connect.
Horizontal Cross-Connect (HC)
A cross-connect of horizontal cabling to other cabling, e.g., horizontal, backbone or equipment. Could be a patch panel or LAN (small) panel.
Horizontal Length (HL)
The cable distance from the information outlet to the blue field of the cross connect. In SYSTIMAX� SCS, this is referred to as the Horizontal Subsystem.
Horizontal Runs
The part of the premises distribution system installed on one floor that includes the cabling and distribution components connecting the riser backbone or equipment wiring to the information outlet.
Horizontal Stripe
A colored stripe running horizontally with the axis of a conductor, sometimes called a longitudinal stripe, used as a means of circuit identification.
Horizontal Subsystem
The part of a premises distribution system installed on one floor that includes the cabling and distribution components connecting the Riser backbone Subsystem to the information outlet via cross-connect components of the Administration Subsystem.
Horn Antenna
A microwave antenna made by flaring out the end of a circular or rectangular waveguide in the shape of a horn. It is used for radiating radio waves into space.
HOST
Term describing a Host computer. A central computer responsible for the control of time-share terminals and other peripherals. Usually associated with minicomputers and mainframes.
Host Computer
1) A computer attached to a network providing primarily services such as computation, database access or special programs or programming languages.��2) An information processor which provides supporting services and/or guidance to users and/or satellite processors, terminals and other subsidiary devices. A host processor generally is assumed to be self-sufficient and to require no supervision from other processors.��3) Compare with communications computer.
Hot Dip
A term denoting the covering of a surface by means of dipping the surface to be coated into a molten bath of the coating material.
Hot melt
A type of connector pre-loaded with epoxy. The connector must be heated to liquefy epoxy for fiber optic insertion. The ferrule is then cooled to re-harden the epoxy. Manufactured by 3M.
Hot Stamping
Method of alpha numerical coding. Identification markings are made by pressing heated type and marking foil into softened insulation surfaces. See Surface Printing .
Hot-melt adhesive
A thermoplastic adhesive that is applied in a molten state and forms a bond upon cooling to a solid state.
Hot-setting adhesive
A thermoplastic adhesive that is applied in a molten state and forms a bond upon cooling to a solid state.
Housing Connector
Connectorless insert but with insert retaining and positioning hardware required by standard construction. (MIL-STD)
Hub Activation
Hub activation tests transmit a signal to a 10 BASE-T hub to verify it is operational.
Hum
A term used to describe 60 or 120 cycle sound present in the sound of some communication equipment, usually the result of either undesired coupling to 60 cycle source or defective filtering of 120 cycle rectifier output.
Hybrid Cable
An assembly of two or more different types of cable units, cables or categories covered by an overall sheath. It may be covered by an overall shield.
Hybrid Fiber Coax (HFC)
A hybrid system, used by the CATV industry, that employs a fiber optic backbone and coax cables for final distribution from the node to the customer.
Hypalon®
Dupont's trade name for their chlorosulfonated polyethylene, an ozone resistant synthetic rubber.
Hysteresis
The lag between a cause and effect; temperature change and resultant electrical phase changes in cable when the temperature returns to the initial point of measurement.