Honeywell ST 3000 User Manual
Page 95

B.1
North American Classification of Hazardous
Locations,
Continued
Methods of Protection
The following table summarizes available methods of protection for use
in given locations.
Protection Concept
Designation
Permitted Use
Principle
Explosionproof
XP
Division 1 & 2
Contains explosion and
quenches flame.
Intrinsic Safety
IS
Division 1 & 2
Limit energy of sparks under
normal and fault conditions.
Pressurized
Type X and Y
Division 1
Keeps flammable gas out.
Pressurized
Type Z
Division 2
Keeps flammable gas out.
Nonincendive
NI
Division 2
No arcs, sparks or hot surfaces
under normal conditions
Temperature
Classification
Equipment intended for installation directly within the hazardous
location classification must also be classified for the maximum surface
temperature that can be generated under normal or fault conditions as
referenced to either 40°C (104°F) or the maximum operating ambient of
the equipment (whichever is greater). The maximum surface
temperature must be less than the minimum autoignition temperature of
the hazardous atmosphere present. The temperature shall be indicated in
identification numbers as listed in the following table.
Maximum
Temperature
Degrees C
Degrees F
Identification Number
450 842 T1
300 572 T2
280 536 T2A
260 500 T2B
230 446 T2C
215 419 T2D
200 392 T3
180 356 T3A
165 329 T3B
160 320 T3C
135 275 T4
120 248 T4A
100 212 T5
85 185 T6
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2/05
ST 3000 Release 300 Installation Guide
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