• Author / Uploaded
• Jennifer Scott

Citation preview

Marking of Weighing Equipment for Hazardous Areas Typical Marking Example Explosion Protection Marking

Group / Class, Area Classification

Protection Method

Explosion Group

Temperature Class

II 2 G/D

Ex ib

IIB

T4

Ex ib Class I Zone 1

IIB

Directive

Legislation

ATEX

T4

Da

IEC / CENELEC (Europe)

IECEx

IIB

T4

FM

NEC 505

Group A, B, C, D, E, F

T4

FM / UL

NEC 500

AEx ib

Class I, II, III Division 1

EPL*

(USA)

(USA) *Equipment Protection Level

Group, Area Classification CENELEC / IEC / ATEX Equipment Group

Area Classification ATEX 94/9/EC

Equipment Protection Level

II

ATEX

CENELEC/ IEC

Gas / Vapor

Dust

1G/1D*

Ga/Da*

Zone 0

Zone 20

Protection Method Explosive atmosphere present

Continuously or for long periods of time

2G/2D*

Gb/Db*

Zone 1

Zone 21

Occasionally in normal operation

3G/3D*

Gc/Dc*

Zone 2

Zone 22

Infrequently or for short periods of time

Classified Area

Type of Protection

Symbol

Increased Safety

Ex e

Temperature Class

Division 2

Maximum Surface NEC 500 Temperature

Explosive atmosphere present

NEC 506/ CENELEC

Zone 0

Zone 20

Continuously or for long periods of time

450ºC

T1

T1

Zone 1

Zone 21

Occasionally in normal operation

300ºC

T2

T2

Zone 22

Infrequently or for short periods of time or do not likely to occur in normal operation

Zone 2

Explosion Substance Group NEC / IECEX / ATEX Equipment Classification

Substance

Substance Group

Acetylene

A

Hydrogen

B Class I

Ethylene

C

Propane

D

Methane

Mining

Conductive Dusts

E Class II

F

Non-conductive Dusts Combustible Fibers and Flyings

IECEx / ATEX Group

Class III

IIC IIB

500

IIA

IIIC

G

IIIB

–

IIIA

280ºC

T2A

260ºC

T2B

230ºC

T2C

215ºC

T2D

200ºC

T3

Pressurized

505

Remote Weighing Display

Application Terminal

II 1 G

1

II 2 G

1

II 3 G

2

1, 2

II 1 G

1

II 2 G

1

II 3 G

2

Keep the explosive atmosphere away from the ignition source

II 2 G II 3 G

1 2

Ex nA

non-sparking device

II 3 G

2

Ex nC

sparking devices and components

II 3 G

2

restricted

II 3 G

2

Ex mb Ex “m”

Keep the explosive atmosphere away from any source of ignition

Ex mc

Ex o Ex “o”

T3

1 2

II 2 G II 3 G

Ex ma

Oil Immersion

II 2 G II 3 G

IEC EN 60079-7 ISA/UL 60079-7

IEC EN 60079-11 UL 60079-11 FM 3610

IEC EN 60079-2 UL 60079-2 FM 3620

IEC EN 60079-18 ISA/UL 60079-18

IEC EN 60079-6 ISA/UL 60079-6 FM 3600

IEC EN 60079-15 ISA/UL 60079-15 FM 3600

180ºC

T3A

165ºC

T3B

Ex nR

160ºC

T3C

Ex nL

limited Energy

II 3 G

2

135ºC

T4

Ex d

120ºC

T4A

Flame Proof

Contain the explosion, quench the flame

II 1 G II 2 G

1 2

IEC EN 60079-1 ISA/UL 60079-1

100ºC

T5

Protection by enclosure

tD

Special enclosure design, measuring equipment

II 1 D II 2 D

1 2

IEC EN 61241-1 IEC EN 60079-31

85ºC

500

Purge enclosure with the inert pressurized air

Ex p

Encapsulation

Protection „n“

T4

T5

T6

T6

Ex “n”

Ex “d”

Ex “tD”

Hazardous Area

Safe Area

Hazardous Area

Limit energy; no sparks or surface temperature

Ex ib

NEC

I

Combustible Metal Dusts

Dust / water tight enclosure

NEC 505 / CENELEC

NEC 505 / CENELEC

Division 1

Intrinsic Safety

Standard

Category Division

Ex ic

Area Classification NEC500

Principle

Ex ia

*G = Gas / D = Dust

Class, Area Classification NEC 500/ 505 /506

Design

Safe Area Communication Interface Module

Application Terminal

Communication Interface Module

RS232 Printer RS232 Tank on Weigh Modules

RS232 PC connection

I/O Control

Junction Box

Remote Terminal

AC Source Power Supply

Hazardous Solutions Zone – 1/21, Division 1

Ethernet

Power Supply

RS232 Printer

Crossed Ethernet cable

Analog Platform PC connection Hazardous Solutions Zone – 1/21, Division 1

www.mt.com/ind-wp-intrinsic-safe