6-5
Chapter 6: Cautions regarding Explosion-Proof Models
3. Class II, Division 1 locations
3.1 Wiring methods
• Threaded rigid metal conduit, threaded steel intermediate metal conduit, or Type MI cable with termina-
tion fittings approved for the location, can be employed.
3.2 Sealing
• Where a raceway provides communication between the apparatus enclosure and an enclosure that is not
required to be dust-ignition-proof, a sealing method must be provided to prevent the entrance of dust into
the dust-ignition-proof enclosure through the raceway. One of the following methods can be used: (1) a
permanent and effective seal; (2) a horizontal raceway not less than 10 ft (3.05 m) long; or (3) a vertical
raceway not less than 5 ft (1.52 m) long and extending downward from the dust-ignition-proof enclosure.
• Seals are not required to be explosion-proof.
4. Class II, Division 2 locations
4.1 Wiring methods
• Rigid metal conduit; intermediate metal conduit; electrical metallic tubing; dust-tight wireways; Type MC
or MI cable with approved termination fittings; Type PLTC in cable trays; Type ITC in cable trays; or Type
MC or TC cable installed in ladder, ventilated trough, or ventilated channel cable trays in a single layer,
with a space not less than the larger cable diameter between the two adjacent cables, can be employed.
4.2 Sealing
A sealing method must be provided as shown in 3.2.
5. Class III, Division 1 locations
5.1 Wiring methods
• Rigid metal conduit, rigid non-metallic conduit, intermediate metal conduit, electrical metallic tubing,
dust-tight wireways, or Type MC or MI cable with approved termination fittings, can be employed.
5.2 Sealing
A sealing method is not required.
6. Class III, Division 2 locations
6.1 Wiring methods
Wiring methods must comply with 5.1.
6.2 Sealing
A sealing method is not required.
To Next Page
Loading...
Need help?
General
