Cut Sheet

Rigid and Intermediate Metal Conduit Fittings
For Threaded Rigid Metal Conduit/IMC/PVC Coated Rigid Metal Conduit.
Application
• To connect threaded metal conduit (ferrous rigid/non-ferrous rigid/
PVC coated/or intermediate metal) to a threadless opening in a box
or enclosure in outdoors or indoor location exposed to continuous
or intermittent moisture
• To positively bond conduit to box or enclosure
Features
• Rugged steel/malleable iron/copper-free aluminum construction
• Tapered internal threads for water-tight/dust-tight union (A)
• Threads relieved to prevent bottoming of conduit, ensuring
sound assembly (B)
• Recessed sealing ring at box end; sealing ring captivated (C)
• Hardened steel/malleable iron/copper-free aluminum locknuts
designed to provide high-quality ground continuity; extended reach
of locknut permits clamping on thin boxes and enclosures (D)
• Insulated throat, insulates conductors, prevents abrasion
and thinning of conductor insulation, reduces wire pull effort (E)
• Suitable for hazardous location use per following:
(i) Class I Division 2, Class II Division 1 & 2, Class III Division
1 & 2 per NEC 501-4 (b); 502-4 (a) and 503-3 (a)
(ii) Class II Groups E, F, G, & Class III locations per CEC 18-202;
18-252; 18-302; 18-352
National Electrical Code
®
states that, “Where practical, dissimilar metals in
contact anywhere in the system shall be avoided to eliminate the possibility
of galvanic action.” The only exceptions, aluminum fittings and enclosures,
are permitted to be used with steel conduit.
Joint Industrial Council (JIC) Electrical Standards also forbid dissimilar
metals in contact for the same reason and require that the fittings for
metal conduit be of malleable iron or ductile iron and have impact strength
comparable to that of the conduit.
Threaded Hubs (Bullet
®
Hubs)
(B)
(C)
(E)
Predetermined
Compression
370 Series
370AL Series
Copper-Free Aluminum
Copper free aluminum castings for fittings have a maximum of 0.4%
copper. The most detrimental effect of higher percentage of copper on
aluminum base alloy is its decrease in corrosion resistance.
Standard Material
370-401 Series 370AL
Body:
1
⁄2" thru 1" Steel All Copper-Free Aluminum
1
1
⁄4" thru 6" Malleable Iron
Locknut:
1
⁄2" thru 2" Steel (hardened)
1
⁄2" thru 2" Steel (hardened)
2
1
⁄2" thru 6" Malleable Iron 2
1
⁄2" thru 4" Copper-Free
Aluminum
Screws: Steel (hardened)
O-Ring: Buna N
Insulator: Nylon
Coating: PVC
Standard Finish
370-401 Series 370AL
Hub: Electro Zinc Plated As Cast
Chromate Coated
Locknuts: All Ferrous Locknuts Electro Zinc Plated and Chromate Coated
Screws: All Electro Zinc Plated and Chromate Coated
Range
370 Series:
1
⁄2" thru 6" Conduit
370AL & 401 Series:
1
⁄2" thru 4" Conduit
All hub threads — straight pipe
All female threads — taper pipe (NPT)
Listing/Compliances
UL (UL File No: E-23018)
CSA (LR-637, LR-23086)
UL 514B
CSA C22.2 No. 18
NFPA 70
NEMA FB-1
JIC EGP1; JIC EMP 1
Federal Specification A-A-50553
Federal Standard H-28 (Threads)
A-15
United States
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800.816.7809
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Technical Services
Tel: [phone]
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(D)
(A)