Metal Clad Cable, Armored Cable and Flexible Metal Conduit Fittings Metal Clad Cable, Armored Cable and Flexible Metal Conduit All armored cables may employ copper or According to NEC 320 where armored cable Armored Cable (Type AC) Ref. NEC Article 320 aluminum or copperclad aluminum conductors is terminated, a fitting is required to protect with the following sizes and are rated for conductors from abrasion. In addition, a bushing National Electrical Code defines type AC armored 600 volts or less: is required between the conductors and armor. cable as, A fabricated assembly of insulated Design of fitting has to be such that the conductors in a flexible metallic enclosure. No. 14 AWG to No. 1 AWG Copper insulating bushing is visible for inspection. ACT Indicates an armored cable No. 12 AWG to No. 1 AWG Aluminum Bushing is not required with lead-covered or Copperclad Aluminum employing conductors having cables when properly installed. thermoplastic (Type T) insulation. Type AC cables except ACL carry an internal Portions of this section reprinted by bonding strip of copper or aluminum in intimate AC Indicates an armored cable permission from NFPA 702005, National contact with the armor for its entire length. employing conductors having Electrical Code , Copyright 2004, National Armored cable can be used for both exposed rubber insulation of code grade. Fire Protection Association, Boston, MA. or concealed locations. With lead-covered ACH Indicates an armored cable Please refer to the following for further conductors (Type ACL), the cable can be employing conductors having details and complete information: embedded in masonry or concrete and can be rubber insulation of the heat used in damp locations or where exposed to oil. 1. NEC Article 320Armored Cable resistant (75 C) grade. (Type AC Cable) Armored cable is not permitted in locations ACHH Indicates an armored cable where it will be subjected to physical damage 2. UL 4, ANSI C33.9Safety Standards employing conductors having or corrosive fumes. Armored cable cannot be for Armored Cable rubber insulation of the heat used for direct burial in earth. 3. UL 514B, Safety Standards for Outlet resistant (90 C) grade. With minor exceptions, armored cable is also Boxes and Fittings ACU Indicates an armored cable not permitted to be used in hoists or elevators, employing conductors having 4. A-A-50552Federal Specification. storage battery rooms, any hazardous locations, Fittings for Cable, Power, Electrical rubber insulation of latex grade. in commercial garages and in theaters or similar and Conduit, Metal, Flexible L Used as a suffix, it indicates that locations. a lead covering has been applied 5. NEMA FB-1Standards Publication. Codes require that cable shall be supported Fittings & Supports for Conduit and over the conductor assembly. with straps or staples without damaging Cable Assemblies conductors and also limit the minimum bend 6. CEC Section 12-700Wiring Methods radius to 5 times the diameter of type AC cable. (Armored Cable) Certain precautions are prescribed in code where cable is installed through joist rafters or similar 7. CSA C22.2 No. 51Safety Standards wood members. for Armored Cables 8. CSA C22.2 No. 18Safety Standards for Outlet Boxes, Conduit Boxes and Fittings NOTE The materials herein, whether relating to the National Electrical Code, the Underwriters Laboratories, Inc. listing, to industry practice or otherwise, are not intended to provide all relevant information required for use and installation of our products. Refer to applicable codes, instructions and industry specifications prior to installation or use. United States Technical Services Tel: 901.252.8000 Tel: 888.862.3289 800.816.7809 A-155 www.tnb.com Fax: 901.252.1354Metal Clad Cable, Armored Cable and Flexible Metal Conduit Fittings Metal Clad Cable, Armored Cable and Flexible Metal Conduit continued Flexible Metal Conduit Ref. NEC Article 348 Flexible metal conduit can be used for exposed Flexible metal conduit longer than six feet Please refer to the following for further details or concealed work in dry locations. It can be is permitted to be used as a grounding means and complete information: used for wet locations provided conductors provided the conduit and the fitting are approved 1. NEC Article 348Flexible Metal Conduit within are lead covered or other approved type. for the purpose. To date, there is no flexible 2. UL 1, ANSI C33.92Safety Standards metal conduit approved for the purpose by Flexible metal conduit cannot be used for Flexible Metal Conduit the Underwriters Laboratories. underground or embedded in poured concrete 3. UL 514B, Safety Standards for Outlet or aggregate. With rubber covered conductors, In Class I & II, Division 2 hazardous areas, the Boxes and Fittings the conduit cannot be exposed to oil, gasoline conduit itself cannot be used as the grounding or other materials having a deteriorating effect means. A bonding jumper must be installed in 4. A-A-50552Federal Specification. Fittings on rubber. accordance with NEC Section 250.102. Flexible for Cable, Power, Electrical and Conduit, metal conduit is available with steel or aluminum Metal Flexible With minor exceptions use of flexible metal 5 armor in trade size 16 to 4 . With few exceptions conduit is not permitted in hoists, in storage 5. WW-C-566Federal Specification. 5 3 where 16 and 8 trade sizes are used, Code battery rooms and in any hazardous locations. Conduit, Metal, Flexible prohibits use of conduit less than trade size. Use of flexible metal conduit is restricted to 6. NEMA FB1Standards Publication. Bends in concealed work are restricted to 360 systems under 600 volts. Fittings and Supports for Conduit degrees total. No angle connectors are permitted According to NEC Article 350-5, flexible metal and Cable Assemblies in concealed raceway installations. conduit no longer than six feet and containing 7. CEC 12-1100Wiring Method (Rigid Portions of this section reprinted by circuit conductors protected by overcurrent & Flexible Conduit) permission from NFPA 70-2005, National device rated for 20 amps or less is suitable Electrical Code , Copyright 2004, National Fire 8. CSA C22.2 No. 56Safety Standards for as a grounding means provided, it is terminated Protection Association, Boston, MA. Flexible Metallic Conduit and Liquid-Tight in fittings approved for the purpose. Flexible Metal Conduit 9. CSA C22.2 No. 18Safety Standards for Outlet Boxes, Conduit Boxes and Fittings Suggested Specifications for Armored Cable and Flexible Metal Conduit Fittings Armored cable (metal clad cable type Where armored cable or flexible AC) and flexible metal conduit shall metal conduit terminates into a conform to provisions of following threadless or threaded opening, it applicable standards: shall be assembled with approved fittings fittings shall be of malleable Armored CableUL 4/ANSI iron/steel construction, electro zinc C33.9/CSA 22.2 No. 51 plated inside outside, equipped with nylon insulated throat and shall be of Series 3110 Flexible Metal ConduitUL 1/ANSI Armored Cable Connector angled saddle type as manufactured C33.92/WW-C-566/CSA 22.2 No. 56 & Flexible Metal Conduit by Thomas & Betts, series 3110. Direct bearing screw type fittings Type of cable used and conductors shall not be used within flexible metal conduit shall be suitable for conditions of use Suitable bushing as manufactured and location. by Thomas & Betts, series 422 or 390, shall be provided between Where approved armored cable or the conductors and armor flexible metal conduit is used as an equipment grounding conductor, terminating fitting used shall be of Series 390 the grounding type as manufactured Anti-Short Bushing by Thomas & Betts, series 3110 United States Technical Services Tel: 901.252.8000 Tel: 888.862.3289 800.816.7809 A-156 www.tnb.com Fax: 901.252.1354