Azbil AVP200, Руководство пользователя

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6-4
Installation of an Explosion-proof or Dust-ignition-proof Apparatus
(reproduced from the NEC)
CAUTIONS
•
Install the apparatus only in hazardous (classified) locations for which the apparatus has been approved.
•
The sealing must be a maximum distance of 18 in. (457 mm) from the enclosure.
•
Do not open the apparatus enclosure when an explosive atmosphere is present.
1. Class I, Division 1 locations
1.1 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
•
Threaded joints must be made up of at least five threads fully engaged.
1.2 Sealing
•
The sealing must be a maximum distance of 18 in. (457 mm) from the enclosure.
•
The sealing of each conduit can be provided with a sealing fitting approved for Class I locations.
•
The sealing compound must be approved and must not have a melting point of less than 93 °C (200 °F).
•
The minimum thickness of the sealing compound must not be less than the trade size of the conduit, and
must not under any circumstances be less than 5/8 in. (16 mm).
•
Splices and taps must not 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; Type
PLTC cable in accordance with the provisions for remote-control, signaling, and power-limited circuits
(see NEC, Article 725); Type ITC cable in cable trays, in raceways, supported by messenger wire, or directly
buried where the cable is listed for this use; or Type MI, MC, MV, or TC cable with approved termination
fittings can be employed.
2.2 Sealing
•
Each conduit entering the apparatus enclosure is must be sealed as shown in 1.2.