AUTOHELM ST50 PLUS Instruction Manual
Autohelm
GPS
&
NAVDATA
Operation
and
Installation
Autohelm and
SeaTalk
are
registered
Trade Marks
of
Nautech
Limited
Autohelms
policy
of
continuous
improvement
and
updating
may
change
product
specifications
without
prior
notice
Copyright
Nautech
1993
Package
Contents
The
following
items
are
included
in
the
ST50
Plus
GPS
and Navdata
packages
:
1
.
ST50
Plus
control
head
2
.
Fixing
studs
(2
off)
3
.
Thumb
nuts
(2
off)
4
.
Control
head
cover
5
.
Power
cable
6
.
NMEA
cable
7
.
Security
sticker
8
.
Fitting
template
9
.
Operation
and
Installation
handbook
10
.
Worldwide
Service
Centre
handbook
11
.
Warranty
document
Contents
Introduction
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1
Chapter
1
:
Control
Head
Installation
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3
1
.1
Siting
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3
1
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Mounting
Procedure
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4
1
.3
Power
Supply
(stand-alone
operation)
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6
1
.4
Power
Supply
(SeaTalk
operation)
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6
1
.5
Connection
of
Separated
Instruments
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7
1
.6
Ring
Connection
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8
1
.7
Connection
to
SeaTalk
Compatible
Autopilots
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8
1
.8
Connection
to
a
Position
Transducer
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9
Chapter
2
:
Fault
Finding
and
Maintenance
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11
2
.1
Fault
Finding
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.11
2
.2
Maintenance
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.12
Chapter
3
:
Operation
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13
3
.1
Display
key
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.14
3
.2
Waypoint
Display
and
Entry
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.16
3
.3
Sail
Plan
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.17
3
.4
Man
Overboard
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22
3
.5
Anchor
Watch
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23
3
.6
Dead
Reckoning
Mode
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24
3
.7
Operation
with
SeaTalk
Autopilots
.................
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25
3
.8
Operation
with
a
Navcenter
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26
3
.9
Position
Correction
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27
3
.10
Display
Contrast
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28
Chapter
4
:
CODE
Lock
Security
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29
Chapter
5
:
Calibration
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33
5
.1
Initial
Calibration
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34
5
.2
Intermediate
Calibration
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36
5
.3
Extended
Calibration
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38
Chapter
6
:
General
Specification
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39
Introduction
The
ST50
Plus
GPS
and Navdata
instruments
are repeaters
that
receive
positional
fixes
via
either
NMEA
or
SeaTalk,
from
the
GPS
satellite
system
or
the
Loran/Decca beacon
network
.
The
GPS
system
comprises
of
24
satellites
(operating
globally
24
hours a
day)
grouped
into six
separate
orbits
.
Up
to
5
of
the
24
satellites
are
tracked
at
any one
time,
and
the
difference
between
the unique
signal
from
each
satellite
is
used
by
the
ST50
Plus
GPS
receiver to
calculate
your
exact
position
.
The
ST50
Plus
GPS
and
Navdata
units
also
incorporate
a
security
feature
designed
to
protect
instruments
mounted
in
vulnerable areas,
such as
the
cockpit
or
helm
.
Thank
you
for
purchasing
an Autohelm
product
.
May
we
take
this
opportunity
to
wish you
years
of
trouble
free
operation
.
Chapter
1
:
Control
Head
Installation
1 .1
Siting
The
ST50
Plus
GPS/Navdata
is
designed
for
above
or
below
deck
installation
where
it
is
:
"
Easily
readable
by
the
helmsman
"
Protected
against
physical
damage
"
At
least
230mm
(9in)
from
a
compass
"
At
least
500mm
(20in)
from
radio receiving
equipment
"
Accessible
from
behind
for
ease
of
installation
and
cable
running
Caution
:
To
prevent
moisture
forming
on
the
display
window,
the
ST50
Plus
GPS/Navdata 'breathes'
through
a
small
vent
in
the
cable
boss
.
Therefore,
the
control
head
mustbe
sited
where
the
rear
case
is
protected
from
contact
with
water
.
The
rear
case
is fitted
with
afoam
gasket
to
form
a
water-tight
seal
between
the
instrument
and
the
selected
installation
face
.
1
Cable
boss
2
Fusing
studs
3Thumb
nuts
4
Gasket
1
.2
Mounting
Procedure
1
.
Make
sure that
the
selected
location
is
clean,
smooth
and
flat
.
2
.
Apply
the
self-adhesive
template
(supplied)
to
the
selected
location
and
mark
the
centres
for
the
fixing
studs
(2)
and
the
cable
boss
(1)
.
3
.
Drill
two
4mm
(5/32in)
clearance
holes
for
the
fixing
studs
(2)
through
the
bulkhead
.
Remove
the
template
.
4
.
Cut
the
clearance
hole
for
the
cable
boss
(1)
using
a
50mm
(2in)
diameter
cutter
.
5
.
Screw
the
two
fixing
studs
(2) into
the
control
head
.
6
.
Pass
the
SeaTalk
cable
and
transducer
tails
through
the
cable-boss
(1)
clearance hole
.
7
.
Assemble
the
control
head
to
the
bulkhead
and secure from
behind
using
the
thumb
nuts
(3)
.
Bracket
Mounting
The
ST50
Plus
GPS/Navdata
can,
as an
alternative,
be
bracket
mounted
using
the
Autohelm
Mounting
Kit
(Catalogue
No
.
D130)
.
Note
:
Because
the
instrument
breathes
through
the
vent
in
the
rear
case,
this
bracket
is
for
interior
use
only
.
Flush
Mounting
A
flush
mounting
kit
is
available
for
installations
where
a
flush
mount
is
required or
more
desirable
.
Full
installation
instructions
are
provided
with
the
kit
(Catalogue
No
.
D187)
.
1
.
3
Power
Supply
(stand-alone operation)
1
.
Connect
the
2m
(6ft
.)
power
supply
cable
to
the
distribution
panel
.
2
.
Cut
the
cable
to
length
and connect
the
red
wire to
the
+12V
terminal
and
screen
to
the
OV
terminal
.
3
.
Cut
back
and
insulate
the yellow
wire
.
4
.
Protect
the
circuit
with
a
5A
circuit
breaker
.
Longer
runs
to
the
vessels
power
supply
can
be
made
using
one
of
the
SeaTalk
Extension
Cables
.
1
.4
Power
Supply
(SeaTalk
operation)
All
instruments
in
a SeaTalk
system
receive
power
and
information
from
the
SeaTalk bus
.
Each
instrument
has
two
SeaTalk
connectors
(3
pin)
on
150mm
(6in)
tails
.
To
supply
power
and
information
to
the
instrument
simply plug
the
tails
from
adjacent
instruments
into
the
ST50 GPS/
Navdata
tails
.
1
.5
Connection
of
Separated
Instruments
Separated
instruments
can be
connected
using
one
of
the
range
of
SeaTalk
Extension
Cables
.
These
cables
are
supplied with
a SeaTalk
connector
fitted
to
each
end
.
A
junction
box
can
be
used
to
join
the
cable
if
it
is
cut
for
easier
routing
or
shortening
.
If
preferred,
any 2
core,
screened
cable
conforming
to
the
following
specification
may
be used
instead
of
the
SeaTalk
cable
.
"
22
AWG,
2
core
screened
cable
with
a
minimum
copper
area
of
0
.5mm
2
.
1 .3
Power
Supply
(stand-alone operation)
1
.
Connect
the
2m
(6ft
.)
power
supply
cable
to
the
distribution
panel
.
2
.
Cut
the
cable
to length
and connect
the red
wire to
the
+12V
terminal
and screen
to
the
OV
terminal
.
3
.
Cut back and
insulate
the yellow
wire
.
4
.
Protect
the
circuit
with
a
5A
circuit
breaker
.
Longer
runs to
the
vessels
power
supply
can be
made
using
one
of
the
SeaTalk
Extension
Cables
.
1 .4
Power
Supply
(SeaTalk
operation)
All
instruments
in
a
SeaTalk
system
receive
power
and
information
from
the
SeaTalk
bus
.
Each
instrument
has
two
SeaTalk
connectors
(3 pin)
on
150mm
(bin) tails
.
To
supply
power
and
information
to
the
instrument
simply
plug
the
tails
from
adjacent instruments
into
the
ST50
GPS/
Navdata
tails
.
1
.
5
Connection
of
Separated
Instruments
Separated
instruments
can be connected
using
one
of
the
range
of
SeaTalk
Extension
Cables
.
These
cables
are
supplied
with
a
SeaTalk
connector
fitted
to
each end
.
A
junction
box
can be
used
to
join
the
cable
if
it
is
cut
for
easier
routing
or
shortening
.
If
preferred,
any 2
core,
screened
cable
conforming
to
the
following
specification
may
be
used
instead
of
the
SeaTalk
cable
.
"
22
AWG,
2 core screened
cable
with
a
minimum
copper
area
of
0
.5mm
2.
1 .6
Ring
Connection
Installations
with
a
large
number
of
instruments
on a
SeaTalk
bus
may
require
a
second
ring-main
connection
to
the
power
supply
breaker
to
prevent
excessive
voltage
drops
.
Whether
a
second
ring
main
is
required
can be
determined
from
the
following
:
Cable
run
upto
10m
(33ft)
Single
connection
:
13
instruments
maximum
Second
connection
:
26
instruments
maximum
Cable
run
upto
20m
(66ft)
Single
connection
:
7
instruments
maximum
Second
connection
:
13
instruments
maximum
The
second
ring-main
should
be
connected
to
the
spare
lead
on
the
last
instrument
in
the
chain
and
directed
back
to
the
circuit
breaker
.
1 .7
Connection
to
SeaTalk
Compatible
Autopilots
If
the
installation
includes
a SeaTalk
compatible
Autopilot,
ST50
Plus
instruments
may
be
connected
to
the
SeaTalk
bus
at
any
point
.
No
independent connection
to
the
12V
power
supply
is
necessary as
the
instruments
receive
power
from
the Autopilot
course
computer
.
1
.8
Connection
to
a
Position
Transducer
The
ST50
Plus
GPS/Navdata
receives basic
navigation information
from
a
position
transducer
via
NMEA
.
The
position
transducer should
be
connected
to
your
SeaTalk
system
in
one
of
the
following
ways
:
1
.
Directly
to
the
ST50
Plus
GPS/Navdata
NMEA
port
.
2
.
Via
an
Autohelm
Navcenter
(NMEA
0183
data
out
port)
Note
:
When
used
with
a
Navcenter,
the
ST50
Plus
Navdata/GPS
can
only
be
used
in
'Repeater
'
mode
(refer
to
Chapter
5,
Calibration
for
details)
.
Refer
to
the
Navcenter
handbook
for
accepted
NMEA
sentences
.
The
Navdata
is
also
capable
of
receiving
navigation information
directly
from
a
Navstar
2000D
Decca
system
.
Connection
is
identical
to
NMEA
but the
instrument
must
be
set up
in
Calibration
to
receive
the
special
Navstar
data
format
(refer
to
Chapter
5)
.
Chapter
2
:
Fault
Finding
and
Maintenance
2
.1
Fault
Finding
All
Autohelm
products
are,
prior
to
packing
and
shipping,
subjected
to
comprehensive
test
and
quality
assurance
programmes
.
However,
if
a
fault
arises
with
the
ST50
Plus
GPS/Navdata,
the
following table
will
help
to
identify
the
probable
cause and
provide
the
most
likely
cure
.
Fault
Cause
Action
Instrument
display
blank
.
No
supply
.
Check
supply
.
Check
cabling
and
security
of
SeaTalk
connectors
.
Check
fuse/breaker
.
Return
unit
for
repair
.
Instrument
displays
'CODELOCK
set',
ENTER
CODE
The
'Code
Lock'
feature
has
been
set
.
Enter
correct
code
number
.
No
navigation
information
.
Loss
off
information
from
position
transducer
.
Check
transducer
signal
status
.
Check
cabling
between
transducer
and
GPS/Navdata
or
N
a
v
ce
nter
No exchange
of
information
between
SeaTalk
instruments
.
SeaTalk
cabling
problem
.
Check
security
of
SeaTalk
connectors
.
Disconnect
instruments
one
by
one
to
isolate
faulty
unit
.
Failure
of
a
group
of
instruments
in
SeaTalk
chain
.
SeaTalk
cabling/connector
problem
.
Check
security
of
SeaTalk
connectors
and
non-functioning
units
.
2
.2
Maintenance
Instrument
Certain
atmospheric
conditions
may
cause
condensation
to
form on
the
control
head
window
.
This
will
not
harm
the
instrument
and
can be
cleared
by
increasing
the
illumination
setting
to
Level
3
.
Chemical
and
abrasive
materials
must
not
be used
to
clean
the
ST50
Plus
GPS/Navdata
instrument
;
if it
is
dirty,
clean
with
a
soft,
damp
cloth
.
Transducer
Refer
to
the
Installation
and Maintenance
instructions
supplied
with
the
transducer
.
Cabling
Examine
all
cables
for
chafing
or
damage
to
the
outer
shield
and,
where
necessary,
replace
and
resecure
.
Advice
For
advice,
or
further
information
regarding the
installation
of
this
product,
please
contact
the
Autohelm
product
Support
Department
or your
own
National
Distributor
.
Chapter
3
:
Operation
The
Navdata/GPS
allows
you
to
enter
and
store
upto
99
waypoints
.
A
route
can
be
constructed
as any
number
of sequential
waypoints
(1, 2,
3
4)
or,
aftematively,
a
single
sail
plan of
up
to
10
waypoints
selected
in
any
order
(e .g
.
2,
4,1)
.
Waypoints
tracked
sequentially
Waypoints
tracked
using
Sail
Plan
The
features
described
above,
together
with
all
the
other
operational
features
of
this
instrument,
are
covered
in
this
section
.
The
primary
displays
are
cycled
using
DISPLAY
or
TRACK
and
related
functions
selected using
the
V
and ^
keys
.
3
.1
Display
key
Other manuals for ST50 PLUS
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