Page 230 - Electrical Installation in Hazardous Area
P. 230
194 Electrical installations in hazardous areas
No conducting framework
I
I
I
I
Maximum area of each of six external surfaces
IIA and llB = 100 cm2
IIC = 20 cm2
Maximum volume
IIA and 118 = 1000 cm3
IIC = 90 cm3
Conducting exposed earthed framework
Maximum area of each of six external surfaces
IIA and llB = 400 cm2
IIC = 100 crn2
Maximum volume
IIA and 118 = 8000 cm3
IIC = 1000 crn3
Fig. 8.2 Insulating plastics enclosures
