Page 311 - Offshore Electrical Engineering Manual

298 CHAPTER 3 Environmental Protection

Table 5.3.1 Ingress Protection Rating Examples
Code First Digit Second Digit
IP20 Contact with live or moving parts or ingress by
objects with diameters of 12 mm and more.
IP24S As above-mentioned. Harmful effects of water
splashed against the motor
from any direction.
IP44 Protection against contact with live or moving Harmful effects of water
parts inside the enclosure by tools, wires or splashed against the motor
such objects of thickness greater than 1 mm. from any direction.
Protection against ingress of small solid foreign
bodies (diameter greater than 1 mm) excluding
the ventilation openings (intake and discharge
of external fans) and the drain hole of enclosed
machine, which may have degree 2 protection.
IPW45S Contact with live or moving parts by objects of Harmful effects of water pro-
1 mm thickness. jected by nozzle against the
Ingress of foreign bodies with diameters of motor from any direction.
1 mm and more, and rain, snow and airborne
particles to an amount inconsistent with correct
operation.
IP54 Complete protection against contact with live Water splashed against
or moving parts inside the enclosure. Protection the motor from any direc-
against harmful deposits of dust. tion shall have no harmful
effects.
IP55 Complete protection against contact with live or Water projected by a nozzle
moving parts inside the enclosure. against the motor from
The ingress of dust is not totally prevented, but any direction shall have no
dust cannot enter in an amount sufficient to harmful effects.
interfere with the satisfactory operation of the
machine.
IP56 As above-mentioned. Motor protected against
conditions on a ship’s deck.
IP65 Complete protection against contact with live or Water projected by a nozzle
moving parts inside the enclosure and against against the machine from
the ingress of dust. any direction shall have no
harmful effects.
IP66 Complete protection against contact with live or Water from heavy seas or
moving parts inside the enclosure and against water projected from jets
the ingress of dust. shall not enter the machine
in any harmful quantity.

cranage available. The lifting capability of an offshore crane will vary depending
on the operating radius of the jib required and the sea state, particularly the wave
height, in which the crane is required to operate. Therefore, if a module weight is
known to be critical, switchgear and other heavy equipment should be installed