Simrad AP21 and AP22 Autopilots
52 20220596G
3.16 IP protection
Each part of a Simrad autopilot system has a two digit IP
protection code.
The IP rating is a method to classify the degree of protection
against solid objects, water ingress and impact afforded by
electrical equipment and enclosures. The system is recognised in
most European countries and is set out in a number of British and
European standards.
The first code number describes the protection against solid
objects, and the second number describes the protection against
liquids.
FIRST NUMBER
Protection against solid objects
SECOND NUMBER
Protection against liquids
IP TESTS IP TESTS
0 No protection 0 No protection
1 Protection against solid objects
up to 50 mm, eg. accidental
touch by hands.
1 Protected against vertically falling
drops of water (eg. condensation).
2 Protection against solid objects
up to 12 mm, eg. fingers.
2 Protected against direct sprays of
water up to 15° from the vertical.
3 Protection against solid objects
over 2.5 mm (tools + wires)
3 Protected against sprays to 60° from
the vertical.
4 Protection against solid objects
over 1 mm (tools + wires +
small wires)
4 Protected against water sprayed
from all directions - limited ingress
permitted.
5 Protection against dust -
limited ingress (no harmful
deposit)
5 Protected against low pressure jets
of water from all directions - limited
ingress permitted.
6 Totally protected against dust 6 Protected against strong jets of
water, eg. for use on shipdecks -
limited ingress permitted.
7 Protected against the effects of
immersion between 15 cm and 1 m.
8 Protected against long periods of
immersion under pressure.