INSERTION LOSS - The total optical power loss caused by the insertion of an optical component such as a connector, splice, or coupler.
INSULATION - That portion which is relied upon in a cable to segregate and protect the conductor from the other conductors, conducting parts, or from ground.
INSULATION LEVEL - The impulse voltage breakdown of cables and equipment.
INSULATION RESISTANCE - The resistance offered by an insulating material to the flow of current resulting from an impressed DC voltage.
INSULATOR - a) A nonconducting substance such as porcelain, plastic, glass, rubber, etc; b) a device made of such material used for separating or supporting conductors to prevent undesired flow of electricity.
INTERAXIAL SPACING - Center to center conductor spacing in paired wire; center to center spacing between conductors in a flat cable.
INTERCOM WIRE - Wire used to connect communication instruments, telephones, telegraphs, etc.
INTERLACED TAPES - Two or more tapes, generally of different composition, applied simultaneously in such a manner that a portion of each tape overlays a portion of the other tape.
INTERSTICE - A space that intervenes between things.
IPCEA - Abbreviation for Insulated Power Cable Engineers Association. Now ICEA.
IPE - Abbreviation for irradiated polyethylene tape.
IRE - Abbreviation for Institute of Radio Engineers, now IEEE.
