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Jack H.Integration and automation of manufacturing systems.2001.pdf
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page 591

26. APPENDIX B - COMMON REFERENCES

26.1 JIC ELECTRICAL SYMBOLS

• The Joint International Committee (JIC) developed a standard set of symbols for representing electrical circuit elements. These are given below:

disconnect

circuit interrupter

 

 

 

 

 

 

(3 phase AC)

(3 phase AC)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

normally open

normally closed

 

 

 

 

 

 

 

 

 

 

 

 

 

limit switch

limit switch

breaker (3 phase AC)

normally open

normally closed

double pole

mushroom head

push-button

push-button

push-button

push-button

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

F

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

thermal

 

 

 

 

 

 

 

 

 

 

overload relay

Fuse

motor (3 phase AC)

 

 

 

 

liquid level

liquid level

vacuum pressure

vacuum pressure

normally open

normally closed

normally open

normally closed

page 592

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

temperature

 

 

 

 

 

 

 

 

 

flow

temperature

flow

normally open

normally closed

normally closed

normally open

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

R

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

indicator lamp

relay

 

 

 

 

 

 

 

 

 

relay coil

contact

relay contact

normally open

normally closed

 

 

 

 

 

 

 

 

relay time delay on

relay time delay on

relay time delay off

relay time delay off

normally closed

normally closed

normally open

normally open

 

 

H1 H3 H2 H4

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

X1

X2

 

horn

 

 

 

buzzer

 

 

bell

 

 

 

 

 

 

 

 

2-H

 

 

 

 

 

control transformer

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

solenoid

 

 

 

 

 

2-position

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

hydraulic solenoid

 

 

 

 

26.2 NEMA ENCLOSURES

• NEMA has provided a set of ratings for cabinets housing voltages less than 1000V AC. The basic classifications are outlined below,

page 593

Type 1 - General purpose - indoors

Type 2 - Dirt and water resistant - indoors

Type 3 - Dust-tight, rain-tight and sleet(ice) resistant - outdoors Type 3RRainproof and sleet(ice) resistant - outdoors

Type 3SRainproof and sleet(ice) resistant - outdoors Type 4 - Water-tight and dust-tight - indoors and outdoors

Type 4X - Water-tight and dust-tight - indoors and outdoors Type 5 - Dust-tight and dirt resistant - indoors

Type 6 - Waterproof - indoors and outdoors

Type 6P - Waterproof submersible - indoors and outdoors Type 7 - Hazardous locations - class I

Type 8 - Hazardous locations - class I Type 9 - Hazardous locations - class II Type 10 - Hazardous locations - class II

Type 11 - Gas-tight, water-tight, oiltight - indoors Type 12 - Dust-tight and drip-tight - indoors Type 13 - Oil-tight and dust-tight - indoors

FACTOR

1

2

3

3R

3S

4

4X

5

6

6P

11

12

12K13

prevent human contact

x

x

x

x

x

x

x

x

x

x

x

x

x

x

falling dirt

x

x

 

 

 

x

x

x

x

x

x

x

x

x

liquid drop/light splash

 

x

 

 

 

x

x

 

x

x

x

x

x

x

airborne dust/particles

 

 

 

 

 

x

x

x

x

x

 

x

x

x

wind blown dust

 

 

x

 

x

x

x

 

x

x

 

 

 

 

liquid heavy stream/splash

 

 

 

 

 

x

x

 

x

x

 

 

 

 

oil/coolant seepage

 

 

 

 

 

 

 

 

 

 

 

x

x

x

oil/coolant spray/splash

 

 

 

 

 

 

 

 

 

 

 

 

 

x

corrosive environment

 

 

 

 

 

 

x

 

 

x

x

 

 

 

temporarily submerged

 

 

 

 

 

 

 

 

x

x

 

 

 

 

prolonged submersion

 

 

 

 

 

 

 

 

 

x

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

*source Omron catalogs - check