Table 51A IEC 364-5-51 indicates the characteristics equipment
necessary according the external influences which the equipment may subjected.2.EXTERNAL INFLUENCES EFFECTING ELECTRICAL EQUIPMENT AND INSTALLATION 81
Table 8.4.3 Characteristics electrical equipment regarding temperature, altitude, presence of
water, foreign solid bodies and corrosive substances.
. such
influences are defined Chapter IEC 364-3.
Code External influences Characteristic required for selection and
erection equipment
A Environmental conditions
AA
AA1
AA2
AA3
Ambient temperature
-60°C +5°C
-40°C +5°C
-25°C +5°C
Specially designed equipment appropriate
arrangements
AA4 -5°C +40°C Normal (in certain cases special precautions may
be necessary)
AA5 +5°C +40°C Normal
AA6 +5°C 60°C Specially designed equipment appropriate
arrangements
AB Atmospheric humidity Under conditions
AC
AC1
Altitude
< 2000 Normal
AC2 2000 May necessitate special precautions such the
application derating factors
Note: For some equipment special arrangements
may necessary altitudes 1000 and
above
AD
AD1
AD2
AD3
AD4
AD5
AD6
AD7
AD8
Presence water
Negligible
Drops
Sprays
Splashes
Jets
Waves
Immersion
Submersion
IP X0
IP X1
IP X3
IP X4
IP X5
IP X6
IP X7
IP X8
AE
AE1
AE2
AE3
Presence foreign solid bodies
Negligible
Small objects (2,5 mm)
Very small objects mm)
IP 0X
IP 3X
IP 4X
AE4 Dust dust penetration not harmful to
functioning equipment
IP dust should not penetrate equipment
AF
AF1
AF2
Presence corrosive polluting substances
Negligible
Atmospheric
Normal
According the nature substances
8. this Commentary.
Equipment characteristics shall determined either degree protection by
conformity tests.3 and
8. Selection and erection electrical equipment according external
influences
Electrical equipment shall selected and erected accordance with the requirements of
Table 51A IEC Publication 364-5-51 (1979), parts which are quoted Tables 8
