COBHAM SAILOR 60 GX, Installation Manual

Page: 145 / 192

Alternative ground for steel hulls
C-4 Appendix C: Ground and RF protection 98-148248-C
C.3 Alternative ground 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.
C.3.1 To ground the ACU
To ground the ACU do as follows:
1. Ground the ACU preferably to the ship with the short cable.
2. Further, ground the ACU at its grounding stud in order to ensure a proper grounding if
the short ADU cable is disconnected.
3. Establish the ground connection either at the hull (recommended) or at a dedicated RF
ground if available (alternative).
The ACU provides galvanic isolation (as required) from its input power terminals to the
chassis/grounding stud. This way the isolated grounding arrangement is maintained.
C.3.2 To ground the ADU
C.3.2.1 Terminal grounded at the hull (recommended)
In this case the ADU is grounded to the ship via one (or more) of its mounting bolts.
1. Make sure to remove painting, dirt, grease etc. at the mounting holes in order to make
good electrical contact to the hull.
2. Use serrated washers when securing the mounting bolts and seal the joint with
protective coating to avoid corrosion.
C.3.2.2 Terminal grounded at a dedicated RF ground (alternative)
In this case the ADU is grounded with a separate ground cable.
1. Route the ground cable parallel and close to the shielded coax cable connecting the
ADU to the ACU grounding kit.
2. You can use a heavy gauge wire with tinned strands (min. 6 mm
2
) for this purpose.
Important
However, bear in mind that the ADU ground
connection must be made at the
same electrical
ground potential as the ACU
(see To ground the
ADU
on page C-4).
Note
For optimum grounding use the mounting bolt located closest
to the ADU cable plate, see
To ground the ADU on page 3-21.