Alternative grounding for steel hulls
98-150471-A02
Appendix F: Grounding and RF protection
F-3
Grounding and
RF
contact to the hull. Use serrated washers when securing the mounting bolts and seal the
joint with protective coating to avoid corrosion.
It is always recommended to establish the shortest possible grounding path e.g. on steel
hulls the ADU should be grounded directly to the hull
2
. However, due to the fact that this is
not possible on e.g. fibreglass hulls (nor is it preferable on aluminium hulls) a number of
alternative grounding methods are suggested in the following paragraphs.
F.3
Alternative grounding for steel hulls
The following guidelines assume a two-wire, isolated grounding arrangement; that is no part
of the circuit, in particular the battery negative, is connected to any ground potential or
equipment.
F.3.1
To ground the ACU
The ACU should preferably be grounded to the ship with the short cable. Further, the ACU
must be grounded at its grounding stud in order to ensure a proper grounding if the short
ADU cable is disconnected.
The ground connection can be established either at the hull (recommended) or at a
dedicated RF ground if available (alternative).
Figure F-2: Grounding the ADU
Note
For optimum grounding use the mounting bolt located closest to the ADU cable
plate, see
2. Please note that the ADU ground connection is made at the same electrical ground potential
as the ACU.
Antenna bottom
Mounting base
M12 bolt
Serrated washer
(stainless steel)
(stainless steel)
Important
However, bear in mind that the ADU ground
connection is to be made at the
same electrical
ground potential as the ACU
(see
SAILOR900HP.book Page 3 Monday, July 18, 2016 12:44 PM
