Safety Yamatake Corporation
vi Model HGC303 - Heat Value Gas Chromatograph
1. Class I, Division 1 locations
1.1 Wiring methods
•Threaded rigid metal conduit, threaded steel intermediate metal conduit, or
Type MI cable with termination fittings approved for the location, can be
employed
•Threaded joints must be made up with at least five threads fully engaged.
• Boxes, fittings, and joints must be approved for Class I, Division 1.
1.2 Sealing
• Each conduit entering the apparatus enclosure is required to be sealed
within 18 in. (457 mm) from the enclosure.
• The sealing of each conduit can be provided with a sealing fitting approved for
class I locations.
•Sealing compound must be approved and must not have a melting point of less
than 93° (200°F).
• The minimum thickness of the sealing compound should not be less than the
trade size of the conduit and, in no case, less than 5/8 in.(16 mm).
• Splices and taps cannot be made in the fittings.
2. Class I, Division 2 locations
2.1 Wiring methods
•Threaded rigid metal conduit, threaded steel intermediate metal conduit,
enclosed gasketed busways, or Type PLTC cable in accordance with the
provisions of remote-control, signaling, and power-limited circuits (see NEC,
Article 725), or Type ITC cable in cable trays, in raceways, supported by
messenger wire, or directly buried where the cable is listed for this use; Type
MI, MC, MV, or TC cable with approved termination fittings can be
employed.
• Boxes, fittings, and joints are not required to be explosionproof.
2.2 Sealing
• Each conduit entering the apparatus enclosure is required to be sealed as shown in 1.2.
3. Class II, Division 1 locations
3.1 Wiring methods
•Threaded rigid metal conduit, threaded steel intermediate metal conduit, or
Type MI cable with termination fittings approved for the location, can be
employed.
• Boxes and fittings must be dusttight.
3.2 Sealing
• Where a raceway provides communication between the apparatus enclosure and
an enclosure that is not required to be dust-ignitionproof, suitable means must be
provided to prevent the entrance of dust into the dust-ignitionproof enclosure
through the raceway. One of the following means 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-ignitionproof enclosure.
• Seals are not required to be explosionproof.
