56
MX 420 Installation and Service Manual
If the external power to the unit fails for any reason, the navigator will remember if it
was on or off for about 20 minutes. That is if the navigator was on when the power
failed and the power comes back within 20 minutes, the navigator will turn itself on
again. Otherwise, it will stay turned off until the key is pressed.
EQUIPMENT INTERFACING
Introduction
The MX420 series is composed of 3 main models, namely:
•
MX420/2
•
MX420/8
•
MX420/AIS
The MX420/2 has two user NMEA ports while the MX420/8 and MX420/AIS have eight
(8) user NMEA ports. All ports are NMEA 0183 protocol capable. Anyone of these ports
can be used to communicate with other external equipment which utilize the NMEA
0183 standard. All NMEA interface ports are configured for RS-422 standard. This
configuration complies with NMEA 0183 version 2.0 and later. The NMEA2 port can be
either as RS-422 or as RS-232. Only one of these two electrical interfaces may be
implemented at any given time on port 2. The RS-232 port standard is used to connect
to a personal computer or any other RS-232 or
single ended interfac
e. The RS-422
electrical interface will almost always work with the older NMEA 0183 version 1.5
electrical interface; both of which are
balanced line interface
s. If for some reason
you can’t get this interface to work, try the Port 2 RS-232 interface.
Other features available only from, the MX420/8 are:
•
External Man-Over-Board (MOB) switch input (also used for external
Event input)
•
Pulse Counter inputs for the speed log,
•
Additional NMEA ports (NMEA 5 through 10)
•
Optional 1 PPS output
Refer to Section 4 of this manual for wiring information.
Note: The MX420/AIS (MKD) is used primarily as a display and
control unit for the MX423 AIS transponder but can also
perform all the navigation features of the MX420/8 when a
MX421 antenna is connected to it.
External Man Over Board & Event (MX420/8 Only)
A momentary closed switch can be connected between the pin 6 (MOB/Event) input
and REF GND on cable B. Connect the appropriate MOB/Event pins to a
normally ope
n
switch.
The Man-Over-Board (MOB) function is activated when the switch is pressed for at
least 2 seconds, causing the two contacts to short. Once activated, the MOB condition
must be canceled from the MX420 front panel display. Refer to the Operator’s manual
for this operation and more details on the Man Over Board function. When this switch
is closed for less than 2 seconds, this causes your present position and time to be
stored as a waypoint in the waypoint bank. A message indicating which waypoint
number is used will be displayed on the MX420 screen for up to 5 seconds in this
scenario.
Summary of Contents for MX420
Page 1: ...Installation Service Manual MX420 Navigation System ...
Page 5: ......
Page 8: ...1 MX 420 Installation and Service Manual List of Components SECTION 1 LIST OF COMPONENTS ...
Page 9: ...MX 420 Installation and Service Manual List of Components 2 ...
Page 15: ...MX 420 Installation and Service Manual List of Components 8 ...
Page 17: ...MX420 Installation and Service Manual Technical Specifications 10 ...
Page 24: ...17 MX420 Installation and Service Manual SECTION 3 MECHANICALAND INSTALLATION DRAWINGS ...
Page 25: ...18 MX420 Installation and Service Manual ...
Page 32: ...25 MX420 Installation and Service Manual SECTION 4 ELECTRICALINSTALLATION DRAWINGS ...
Page 33: ...26 MX420 Installation and Service Manual ...
Page 49: ...42 MX420 Installation and Service Manual ...
Page 57: ...50 MX 420 Installation and Service Manual SECTION 5 INSTALLATION NOTES ...
