Main keywords for this article are NEC Cable Types in Plants. Metal Clad Cables. Types NM and NMC. Type TC CABLE. Type MV Cable and IEC Equivalent. Type PLTC and ITC Cables. Mineral-Insulated Metal-Sheathed Cable.
NEC Cable Types in Plants
Metal Clad Cables
- Metal clad cable (Type MC or armored) is a factory assembly of one or more conductors, each individually insulated and enclosed in a metallic sheath of interlocking tape, or a smooth, or corrugated tube, or steel wires, or braid with overall PVC jacket.
- Type MC cables shall be permitted for use as follows:
a. For services, feeders, and branch circuits; for power, and lighting
b. Indoors or outdoors
c. Where exposed or concealed
d. Direct buried where identified for such use
e. In cable tray
f. In any approved raceway
g. As open runs of cable
h. As aerial cable on a messenger
i. In hazardous locations as permitted in NFPA 70 Articles 501, 502, 503, 504, and 505. j. In dry locations and embedded in plaster finish on brick or other masonry except in damp or wet locations k. In wet locations
Nonmetallic-Sheathed Cable
Types NM and NMC
a. Nonmetallic-sheathed cable (NM) (commonly known as Romex) is an insulated multiconductor cable protected by a nonmetallic sheath or outer covering. The use of nonmetallic-sheathed cable should usually be confined to temporary buildings of wood, masonry block, or tile construction in a non-hazardous location.
b. Type NM cable may be installed for both exposed and concealed work in normally dry nonhazardous areas. Moisture- and corrosion-resistant cable, Type NMC, may be installed for both exposed and concealed work, in dry, moist, damp, and corrosive locations, and in outside and inside walls of masonry block or tile (NFPA 70, Article 336).
Type TC CABLE
Type TC power and control tray cable is a factory assembly of two or more insulated conductors, with or without associated bare or covered grounding conductors under a nonmetallic sheath, approved for installation in cable trays, in raceways, or where supported by a messenger wire. The use of this cable shall be as specified in NFPA 70 Article 340.
Type MV Cable and IEC Equivalent
Medium voltage cable (Type MV) or IEC equivalent is a single or multiconductor solid dielectric insulated cable rated 2001 V or higher as permitted by NFPA 70 Article 326 or the IEC standard. Type MV cables
or IEC cables shall be suitable for use on power systems rated up to 35,000 V in wet or dry locations in raceways, directly buried (when armored), or installed in cable tray. In cable tray, Type MV or IEC cable shall be adequately protected from physical damage.
Type PLTC and ITC Cables
Power-limited tray cable (Type PLTC) and instrumentation tray cable (ITC) are a factory assembly of two or more insulated conductors under a nonmetallic jacket as described in
NFPA 70, Articles 725 and 727, respectively. The insulated conductors shall be a 0.3 mm² (22 AWG) to 4 mm2 (12 AWG).The conductor material shall be copper (solid or stranded). Insulation on conductors shall be suitable for 300 V maximum for Type PLTC, and for 600 V maximum for Type ITC. The cable core shall be:
a. Two or more parallel conductors
b. One or more group assemblies of twisted or parallel conductors, or
c. A combination of a and b
A metallic shield or a metalized foil shield with drain wire(s) shall be permitted to be applied either over the cable core, over groups of conductors, or both. The outer jacket shall be a flame-retardant, sunlight- and moisture-resistant nonmetallic material. This cable shall be installed in cable trays, in raceways. The cable may be directly buried when armored.
Mineral-Insulated Metal-Sheathed Cable
- Mineral-insulated metal-sheathed cable (Type MI) is a cable in which the electrical conductors are insulated with a highly compressed refractory mineral insulation and enclosed in a liquid tight and gas tight metallic tube sheath. Vendor’s instructions shall be followed when installing this type of cable.
- Type MI cable may be used only with SABIC approval.
- Type MI cable, by its construction, inherently prevents the passage of gases, vapors, or flames from one electrical equipment enclosure to another. Sealing compound shall be used in cable termination fittings to exclude moisture and other liquids from the cable insulation.
Main keywords for this article are NEC Cable Types in Plants. Metal Clad Cables. Types NM and NMC. Type TC CABLE. Type MV Cable and IEC Equivalent. Type PLTC and ITC Cables. Mineral-Insulated Metal-Sheathed Cable.