Emerson Bristol 2808 Series, Инструкция по эксплуатации

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2808B Introduction / 1-3
1.3 MODELS APPROVED FOR HAZARDOUS AREAS
Transmitter models certified for operation in hazardous areas by Underwriters
Laboratories (UL) will have the appropriate logo inscribed on the instrument data plate.
These models are intended for use in the following hazardous locations:
Explosion-proof for Class I, Division 1, Groups C and D. (Conduit Seals Not Required)
Nonincendive for Class I, Division 2, Groups A, B, C and D.
The National Electric Code, Article 500, defines the above classes and divisions as follows:
Class I Atmospheres : Contains flammable gases or vapors.
Class II Atmospheres:
Contains combustible dust particles .
Division 1:
Where continuous exposure, or threat of fire or explosion may be present due to accident
or uncommon occurrence.
Division 2:
Where threat of fire or explosion is not normally present, and not likely to result from
abnormal occurrence.
Groups A through D:
Cover various flammable gases and liquids such as ethyl-ether vapor, gasoline, acetone,
etc.
1.4 USING THIS MANUAL
Sections 1A through 1B contain information for specific Transmitter models. These sections
provide information relevant to product description, types of mounting, measurement
applications, service checks, and specifications.
Sections 2 through 5 contain material that pertains to all models; these sections describe
installation, calibration, service and general specifications. The Loop Powered Indicator
option is covered in Appendix B and the Surge Protector option is covered in Appendix C.