Field Service Procedure – Replacement PCU Kit, ST88, ST94 & ST144
Page
16
of
22
Document No
137738 Rev A
Copyright © Sea Tel, Inc 2012 - The information contained in this document is proprietary to Sea
Tel, Inc. This document may not be reproduced or distributed in any form without prior written
consent of Sea Tel, Inc.
20.
Pol
Drive
–
ST88,
ST94
and
ST144:
As
the
pol
aux
relay
is
integrated
into
the
MK2
PCU
motherboard
a
fault
with
the
pol
alignment
could
potentially
be
caused
by
this
PCB.
If
no
pol
drive
is
present
set
the
pol
type
to
manual
mode
(0009),
apply
drive
to
the
feed
assembly
and
measure
the
voltage
to
the
motor
on
the
IDC
connector,
24VDC
should
be
present.
If
voltage
is
present
but
the
motor
isn’t
driving
the
motor
is
defective
and
needs
replacing.
If
no
voltage
is
present
verify
the
connections
of
the
reflector
harness
by
measuring
pin
to
pin
as
per
the
below
diagram.
If
the
harness
connections
are
good,
then
the
PCU
motherboard
isn’t
outputting
the
voltage
to
drive
the
motor
and
needs
replacing.
As
long
as
the
pol
range
is
within
the
pot
limits
the
DAC
will
issue
the
pol
drive
command
to
the
PCU
motherboard,
based
on
the
antenna
targeting,
a
change
in
the
vessels
GPS
position
or
operator
inputs.
The
PCU
motherboard
will
then
drive
the
pol
motor,
which
will
drive
the
feed
until
the
correct
output
from
the
pot
has
been
received.
At
which
point
the
feed
will
be
in
the
correct
reception
position
(providing
the
system
is
functioning
and
calibrated
correctly).
Therefore
there
is
also
the
possibility
for
a
pol
drive
fault
to
be
caused
by
the
PCU
motherboard.
Summary of Contents for ST144
Page 1: ......