255 THOMAS & BETTS, 255 Datasheet - Page 2

• Manufacturer Part Number: 255
• Description: Electrical
• Manufacturer: THOMAS & BETTS

Specifications of 255

• Leaded Process Compatible: No
• Peak Reflow Compatible (260 C): No
• Outer Diameter: 31.75mm
• Length: 38.888mm
• Body Material: Malleable Iron
• External Diameter: 31.75mm
• Accessory Type: Squeeze Connector
• Rohs Compliant: No
• For Use With: Armored Cable And Flexible Metal Conduit
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

A-150
Metal Clad Cable, Armored Cable and Flexible Metal Conduit —
Flexible Metal Conduit — Ref. NEC Article 348
Flexible metal conduit can be used for exposed
or concealed work in dry locations. It can be
used for wet locations provided conductors
within are lead covered or other approved type.
underground or embedded in poured concrete
or aggregate. With rubber covered conductors,
the conduit cannot be exposed to oil, gasoline
or other materials having a deteriorating effect
on rubber.
conduit is not permitted in hoists, in storage
battery rooms and in any hazardous locations.
Use of flexible metal conduit is restricted to
systems under 600 volts.
conduit no longer than six feet and containing
circuit conductors protected by overcurrent
device rated for 20 amps or less is suitable
as a grounding means provided, it is terminated
in fittings approved for the purpose.
Suggested Specifications for Armored Cable and Flexible Metal Conduit Fittings
Flexible metal conduit cannot be used
With minor exceptions use of flexible metal
According to NEC Article 350-5, flexible metal
www.tnb.com
Metal Clad Cable, Armored Cable and Flexible Metal
Conduit Fittings
Armored Cable Connector &
Flexible Metal Conduit
Insuliner
Series 3110
Series 422
®
Sleeve
United States
Tel: [phone]
Fax: [phone]
800.816.7809
is permitted to be used as a grounding means
provided the conduit and the fitting are approved
for the purpose. To date, there is no flexible
metal conduit approved for the purpose by
the Underwriters Laboratories.
conduit itself cannot be used as the grounding
means. A bonding jumper must be installed in
accordance with NEC Section 250.102. Flexible
metal conduit is available with steel or aluminum
armor in trade size
where
prohibits use of conduit less than d" trade size.
Bends in concealed work are restricted to 360
degrees total. No angle connectors are permitted
in concealed raceway installations.
permission from NFPA 70-2005, National
Electrical Code
Protection Association, Boston, MA.
•
•
Flexible metal conduit longer than six feet
In Class I & II, Division 2 hazardous areas, the
Portions of this section reprinted by
Armored cable (metal clad cable type
AC) and flexible metal conduit shall
conform to provisions of following
applicable standards:
Where approved armored cable or
flexible metal conduit is used as an
equipment grounding conductor,
terminating fitting used shall be of
the grounding type as manufactured
by Thomas & Betts, series 3110
Armored Cable…UL 4/ANSI C33.9/CSA 22.2
No. 51
Flexible Metal Conduit…UL 1/ANSI
C33.92/WW-C-566/CSA 22.2 No. 56
Type of cable used and conductors within
flexible metal conduit shall be suitable for
conditions of use and location.
5
⁄
1 6
" and
®
3
⁄
8
, Copyright
" trade sizes are used, Code
5
⁄
1 6
Canada
Tel: [phone]
Fax: [phone]
" to 4". With few exceptions
©
2004, National Fire
Technical Services
Tel: [phone]
Please refer to the following for further details
and complete information:
1. NEC Article 348…Flexible Metal Conduit
2. UL 1, ANSI C33.92…Safety Standards for
3. UL 514B, Safety Standards for Outlet Boxes
4. A-A-50552…Federal Specification. Fittings
5. WW-C-566…Federal Specification. Conduit,
6. NEMA FB1…Standards Publication. Fittings
7. CEC 12-1100…Wiring Method (Rigid &
8. CSA C22.2 No. 56…Safety Standards for
9. CSA C22.2 No. 18…Safety Standards for
•
•
Where armored cable or flexible
metal conduit terminates into a
threadless or threaded opening, it
shall be assembled with approved
fittings; fittings shall be of malleable
iron/steel construction, electro zinc
plated inside outside, equipped with
nylon insulated throat and shall be of
angled saddle type as manufactured
by Thomas & Betts, series 3110.
Direct bearing screw type fittings
shall not be used
Suitable bushing as manufactured by
Thomas & Betts, series 422 or 390,
shall be provided between the
conductors and armor
Flexible Metal Conduit
and Fittings
for Cable, Power, Electrical and Conduit,
Metal Flexible
Metal, Flexible
and Supports for Conduit and Cable
Assemblies
Flexible Conduit)
Flexible Metallic Conduit and Liquid-Tight
Flexible Metal Conduit
Outlet Boxes, Conduit Boxes and Fittings
continued