Navico MX420, MX420/2, MX420/8, MX420/BR, MX420/BRIM Service Manual

MX420 Navigation System

Installation & Service Manual

MX420 Navigation System

Installation and Service Manual

Models Covered:

MX420/2
MX420/8

MX420/BR

MX420/BRIM

MX420/AIS BASIC (MKD)

MX420/AIS DGPS

Prepared by

MX Marine

A Division of NAVICO, Inc.

23868 Hawthorne Boulevard, Suite 201

Torrance, California 90505-5908

USA

P/N 3508 102 70060

July, 2007

MX Marine

MX Marine reserves the right to make changes to its products and specifications without

notice.

 Copyright July, 2007

About This Manual

We at MX Marine have attempted to take care and develop manuals which provide in-depth
information. Obviously, we can’t anticipate every configuration in which you might install the
MX420, but we can help make your work more thorough and enjoyable.

This manual is organized by first describing the list of included items for the particular model
you purchased. The sections that follows detail the technical specifications of the MX420
navigation unit and the MX421 antenna unit. This is followed with the mechanical and electrical
wiring diagrams and installation notes to guide you in the installation of your MX420 system.

Should you require additional technical support, please first contact the dealer where you
purchased your MX420. Since your dealer sells and installs the MX420 and many other types
of equipment, they are often your best resource for technical questions. You can also contact

MX Marine for technical assistance:

International:

We hope you find the manual enjoyable and informative. As always, we welcome your
comments on improving our products or manuals. Thank you.

Product Information

The model and serial number of your instrument are given on the back of the unit. Please enter
the serial number in the space provided below. Always refer to this information when you
contact your dealer.

Model: MX420 Navigation System S/N ___________________

MX Marine (US)

A Division of NAVICO, Inc.
23868 Hawthorne Blvd., Suite 201
Torrance, California 90505
USA

+01-310-791-8213 Telephone (International)
+01-310-791-6108 Fax

[e-mail]
www.mx-marine.com

Notes:

Table of Contents

SECTION 1 - LIST OF COMPONENTS ...................................................... 1

SECTION 2 - TECHNICAL SPECIFICATIONS ............................................ 9

SECTION 3 - MECHANICAL AND INSTALLATION DRAWINGS ............... 17

SECTION 4 - ELECTRICAL INSTALLATION DRAWINGS ........................ 25

Figure 4.1 MX420/2 Basic System Configuration ............................ 27

Figure 4.2 MX420/2 Basic Wiring Diagram ...................................... 28

Figure 4.3 MX420/8 System Configuration ...................................... 29

Figure 4.4 MX420/8 Wiring Diagram .............................................. 30

Figure 4.5 MX420/BR Dual Control System ..................................... 31

Figure 4.6 MX420/BR Dual Control Wiring Diagram ....................... 32

Figure 4.7 MX420/BRIM Dual Station Integrity Monitor System ..... 33

Figure 4.8 MX420/BRIM Dual Station Integrity Monitor Interface

Diagram ............................................................................................. 34

Figure 4.9 Cable (A) Wiring Configuration ...................................... 35

Figure 4.10 Cable (B) Wiring Configuration (Only on MX420/8) ... 36

Figure 4.11 Cable (C) Wiring Configuration (Only on MX420/8) .... 37

Figure 4.12 MX420/2 Rear Panel Connector .................................... 38

Figure 4.13 MX420/8 Rear Panel Connectors .................................. 38

Figure 4.14 MX421(8-Pin) GPS Antenna Wiring Diagram ............... 39

Figure 4.15 MX421-10 (10-Pin) GPS Only Antenna Wiring Diagram40
Figure 4.16 MX421B-10 (10-Pin) DGPS Antenna Wiring Diagram .. 41
Figure 4.17 MX420/AIS CDU & MX423 (SAAB) Transponder System

Block Diagram .................................................................................. 43

Figure 4.18 MX420/AIS CDU & MX423 (SAAB) Transponder System

Wiring Diagram ................................................................................ 44

Figure 4.19 MX420/AIS/MKD CDU & MX531 (ATLAS) Transponder

Block Diagram .................................................................................. 45

Figure 4.20 - MX420/AIS/MKD CDU & MX531 (ATLAS) Transponder

System Wiring Diagram ................................................................... 46

Figure 4.21 MX420/AIS/MKD CDU & MX535 (NAUTICAST) Tran-

sponder Block Diagram .................................................................... 47

Figure 4.22 - MX420/AIS/MKD CDU & MX535 (NAUTICAST) Tran-

sponder System Wiring Diagram ..................................................... 48

Figure 4.23 - MX420/AIS/MKD CDU & MX535 (NAUTICAST) Tran-

sponder System Wiring Diagram with JB-50 Junction Box ............ 49

SECTION 5 ............................................................................................... 50

INSTALLATION NOTES ..................................................................... 50

GENERAL.....................................................................................52

Electronic Connections .................................................................... 52

External Power ........................................................................... 52

Navigator Grounding. ................................................................ 53

MX421 GPS ANTENNA INSTALLATION ........................................... 53

Antenna Location ....................................................................... 53

Antenna Options ........................................................................ 53

Antenna Connector .................................................................... 53

Antenna Cable Options .............................................................. 54

External Differential Connection ................................................ 54

MX420 NAVIGATOR INSTALLATION ................................................ 54

Gimbal Mounting ....................................................................... 55

Flush Mounting .......................................................................... 55

Flush Mount Frame .................................................................... 55

Turning Power On and Off ......................................................... 55

EQUIPMENT INTERFACING........................................................ 56

Introduction .......................................................................... 56

External Man Over Board & Event (MX420/8 Only) ............ 56

Speed Over Ground Pulse Output ....................................... 57

External Alarm Output ......................................................... 57

Port 2: RS- 422 / RS- 232 Serial Interface ............................ 58

MX420 PC Interface .............................................................. 59

NMEA Interface .................................................................... 59

NMEA Interface to other Equipment ................................... 60

MX420 NMEA 0183 Sentences ................................................... 61

Data Format .......................................................................... 61

NMEA Output Sentences ..................................................... 62

Input NMEA 0183 Sentences ............................................... 63

Viewing Input Data ............................................................... 64

Dual Control (Remote) Interface ................................................. 65

MX420 Dual Control with Integrity Monitor .............................. 67

Other MX420/AIS Interface .................................................. 68

MX420 AIS Basic configuration .......................................... 69

MX423 AIS Transponder Interface ....................................... 69

Troubleshooting Guide .............................................................. 69

Memory Backup Battery ............................................................ 71

Backup Battery Replacement ..................................................... 71

MX420 PC Interface .................................................................... 71

Software Download Procedure .................................................. 71

Memory Clear Procedure: .......................................................... 72

List of Components

MX 420 Installation and Service Manual

SECTION 1

LIST OF COMPONENTS

1

MX 420 Installation and Service Manual List of Components

2

List of Components

Item

Component Qty. Part Number

MX421B-10 Smar t DGPS

1

Antenna
MX521 Smart DGPS

2

Antenna

MX521G Smart GPS

3

Antenna

MX525 Smart DGPS

4

Antenna

MX525G Smart GPS

5

Antenna

MX575 D/ GPS Satellite

6

Compass

Table 1.1 Standard Parts for MX420/2 Model

MX 420 Installation and Service Manual

List of Components

Table 1.0 MX Marine Antenna Units

1

9525 200 80110

1

727010

1

727027

1

9525 200 80290

1

9525 200 80291

1

3508 102 70720

Remarks

Option

Option

Option

Option

Option

Option

Item Component Qty. Part Number

1.0 MX420/2 Control and Dis play
System Consisting of:

1.1 MX420, 2 Port Control and Display
Unit

1.2 Mounting Bracket 1 3508 101 38472

1.3 Mounting Kit 1 3508 102 03140

1.4 Power /NMEA Cable (Cable A) 1 3508 102 70010

1.5 MX420 Operator’s Manual 1 3508 102 70040

1.6 MX420 Operator’s Quick Guide 1 3508 102 70050

1.7 MX420 Installation/Service Manual 1 3508 102 70060

1.8 Tide Table Manual 1 3508 101 89490

2.0* MX421 Smart G PS antenna System*
Consisti ng of:

2.1 MX421-10 Smar t GPS Antenna* 1 9525 200 80100 1.1

2.2 Antenna Cable Options:
15 meters
20 meters
40 meters
90 meters

2.3 MX421 Installation Manual 1 723594

*GPS only model. For MX420/2B model substitute with MX421B-10 DGPS Antenna (see table below)

1 9525 200 78000

1 3508 102 70200 2.6

1 Not Included

725637
3508 102 70170
3508 102 70180
3508 102 70190

Wt

(lbs.)

Remarks

with Item 1.0

Option
Option
Option
Option

3

MX 420 Installation and Service Manual List of Components

(

Table 1.2 Standard Parts for MX420/8 Model

Item Component Qty. Part Number Wt.

1.0 MX420/8 Control and Display
System Consisting of:

1.1 MX420, 8 Port Control and Display
Unit

1.2 Mounting Bracket 1 3508 101 38472

1.3 Mounting Kit 1 3508 102 03140

1.4 Power/NMEA Cable (Cable A) 1 3508 102 70010

1.5 Cable B NMEA Cable 1 3508 102 70020

1.6 Cable C NMEA Cable 1 3508 102 70030

1.7 MX420 Operator’s Manual 1 3508 102 70040

1.8 MX420 Operator’s Quick Guide 1 3508 102 70050

1.9 MX420 Installation/Service Manual 1 3508 102 70060

1.10 Tide Table Manual 1 3508 101 89490

2.0* MX421 Smart GPS antenna
System* Consisting of:

2.1 MX421-10 Smart GPS Antenna* 1 9525 200 80100 1.1

2.2 Antenna Cable Options:
15 meters
20 meters
40 meters
90 meters

2.3 MX421 Installation Manual 1 723594

1 9525 200 78010

1 3508 102 70210 2.6

1 Not Included

725637
3508 102 70170
3508 102 70180
3508 102 70190

(lbs.)

Remarks

with Item 1.0

Option
Option
Option
Option

GPS only antenna model. For MX420/8B model substitute with MX421B-10 DGPS antenna

See table below).

4

List of Components

MX 420 Installation and Service Manual

Table 1.3 Standard Parts for MX420/BR Dual Control Display System

Component Qty. Wt.

1.0 MX420/8 Control and Display
System Consisting of:

1.1 MX420, 8 Port Control and Display
Unit

1.2 Mounting Bracket 2 3508 101 38472

1.3 Mounting Kit 2 3508 102 03140

1.4 Power/NMEA Cable (Cable A) 2 3508 102 70010

1.5 Cable B NMEA Cab le 1 3508 102 70020

1.6 Cable C NMEA Cable 1 3508 102 70030

1.7 MX420 Operator’s Manual 2 3508 102 70040

1.8 MX420 Operator’s Quick Guide 2 3508 102 70050

1.9 MX420 Installation/Service Manual 2 3508 102 70060

1.10 Tide Table Manual 2 3508 101 89490

2.0 MX420/2 Control and Display Unit 1 9525 200 78000

3.0* Smart GPS Antenna System
Consisting of :

MX421-10 Smart GPS Antenna

3.1*

Or,
MX421B-10 Smart DGPS Antenna11

3.2 Antenna Cable Options:
15 meters
20 meters
40 meters
90 meters

3.3 MX421 Installation Manual 1 723594

*GPS antenna for MX420/8 GPS only installation use P/N 9525 200 80100. For MX420/8B
DGPS installation use P/N 9525 200 80110.

1 9525 200 78010

1 3508 102 70210 2.6

1Not

9525 200 80100

9525 200 80110

1

725637
3508 102 70170
3508 102 70180
3508 102 70190

Remarks

(lbs.)

Included
with Item

1.0

1.1

1.9

Option
Option
Option
Option

5

MX 420 Installation and Service Manual List of Components

Table 1.4 MX420/BRIM (Integrity Monitor) Model

Item Component Qty. Part Number Wt.

1.0 MX420/8 Control and Display
System consisting of:

1.1 MX420, 8 Port Control and Display
Unit

1.2 Mounting Bracket 2 3508 101 38472

1.3 Mounting Kit 2 3508 102 03140

1.4 Power/NMEA Cable (Cable A) 2 3508 102 70010

1.5 Cable B NMEA Cable 2 3508 102 70020

1.6 Cable C NMEA Cable 2 3508 102 70030

1.7 MX420 Operator’s Manual 2 3508 102 70040

1.8 MX420 Operator’s Quick Guide 2 3508 102 70050

1.9 MX420 Installation/Service Manual 2 3508 102 70060

Tide Table Manual 2 3508 101 89490

1.10

2.0 MX421 Smart DGPS Antenna
System
Consisting of:

2.1 MX421B Smart GPS Antenna 2 9525 200 80110 1.9

2.2 Antenna Cable Options:
15 meters
20 meters
40 meters
90 meters

2.3 MX421 Installation Manual 2 723594

2 9525 200 78010

2 3508 102 70210 2.6

2 Not Included

2

725637
3508 102 70170
3508 102 70180
3508 102 70190

(lbs.)

Remarks

with Item 1.0

Option
Option
Option
Option

6

List of Components

MX 420 Installation and Service Manual

Table 1.5 MX420/AIS Model

Item # Description P/N Remarks

1.0

1.1

1.2 Mounting Bracket 3508 101 38472

1.3 Mounting Kit 3508 102 03140

1.4 Power/NMEA Cable (Cable A) 3508 102 70010

1.5 Cable B NMEA Cable 3508 102 70020

1.6 Cable C NMEA Cable 3508 102 70030

1.7 MX420 Operator’s Manual 3508 102 70410

1.8 MX420 Installation Manual 3508 102 70420

1.9 MX420 Quick Reference Guide 3508 102 70060

1.10 Tide Table Manual 3508 101 89490

1.11 AIS Reference Card

2.0

2.1 MX421B Smart DGPS Antenna 9525 200 80110 Option

2.2

2.3 MX421 Installation Manual 723594

MK420/AIS Control and Display System
Consisting of:
MK420/AIS 8-port Control and Display
Unit

MX421B-10 Smart DGPS Antenna
System
Consisting of:

15 Meter Interface Cable, or
20 meters
40 meters
90 meters

9525 200 80000 Standard

3508 102 70240

725637
3508 102 70170
3508 102 70180
3508 102 70190

Option

Option
Option
Option
Option

7

MX 420 Installation and Service Manual List of Components

8

MX420 Installation and Service ManualTechnical Specifications

SECTION 2

TECHNICAL SPECIFICATIONS

9

MX420 Installation and Service Manual

Technical Specifications

10

MX420 Installation and Service ManualTechnical Specifications

MX421 Smart GPS Antenna

Receiver GPS:

Type: L1, C/ A Code, 12 channel

Update rate: Once per second
Accuracy: 1 m 2DRMS Position with DGPS

Dynamics: Velocity: 460 m/ s

Time to first fix: Less than 1 minute with almanac

Reacquisition: 15 seconds typical
DGPS Input: RTCM SC- 104 format, from internal

continues tracking

3 m 2DRMS without correction

Acceleration: 2.5g

15 minutes from coldstart.

beacon receiver.

Beacon: (MX421B Model)

Type: 2 channels, Automatic or Manual tuning,
Frequency: 283.5 - 325 KHz, in 500 Hz steps
Dynamic Range: 100dB
Adjacent Channel Rejection: 40dB (500 Hz)
Bit rate: 25, 50,100, or 200 (auto- sync)

RTCM Messages Supported: Type 1, 2, 3, 5, 7, 9,16

MX420 Control and Display Unit (CDU)

Display:

Part name: LMG7410PLFC (Hitachi)
Dots: 240 by 128
Duty: 1/ 128
LCD: Film type black and white (negative

Back light: Cold cathode fluorescent lamp
Protection: Acryl 7N PMMA window

Keyboard:

Type: Tactile silicone rubber
Contact: Carbon

Back light: Yellow LEDs

Front enclosure:

Plastic: ABS/ PC- blend Cycoloy C1200

type). Bottom polarizer is trans
missive type. Matches polarized
sunglasses. Viewing dir.: 6 O’clock.

11

MX420 Installation and Service Manual

Back enclosure:

Metal: Cast aluminum

Connectors:

Connector A:
Panel plug: 18-Pin Male (Conxall)
Connector B (MX 420/8 only):
Panel socket: 18-Pin Female (Conxall)
Connector C (MX 420/8 only):

Panel socket: 18-Pin Female (Conxall)

Cables:

Cable A:

Type: 9-Pair Shielded - Wire 24x 0.20 mm
Connector: 18-Pin (Female - Conxall)

Cable B:

Type: 9-Pair Shielded- Wire 24 x 0.02 mm
Connector: 18-Pin (Male - Conxall)

Cable C:

Type: 9-Pair Shielded- Wire 24 x 0.20 mm
Connector: 18-Pins (Male - Conxall)

Antenna:

Type: 8 wire (24 AWG) shielded
Connectors:

Antenna end: 8-Pin Female Conxall
Navigator end: None

Technical Specifications

Antennas:

MX421 GPS Smart Antenna Unit

Freq.: GPS L1 , 1575 MHz

MX421B DGPS Smart Antenna Unit

Freq.: GPS L1 , 1575 MHz
Beacon: 283.5 - 325 KHz

Physical

MX420 CDU:

Height: 145 mm (5.71in)
Width: 271 mm (10.67in)
Depth overall: 53 mm (2.52in)
Depth flush mounted: 24.5 mm (0.98in) to wall
Depth for cables: 100 mm (3 in.)
Weight: 1238 g (2.75 lbs.)
Weight gimbal mount: 214 g (0.47lbs)

12

Cables
Cable A: 2 m (6 ft)

Cable B: 2 m (6 ft)
Canle C: 2 m (6 ft)

MX421 Antenna:

Height: 89 mm (3.27 in)
Diameter: 182 mm (7.28in)
Cable Length:
Supplied: 15 m. (Standard length)

Options: 20 or 40 meters

MX420 Installation and Service ManualTechnical Specifications

13

MX420 Installation and Service Manual

Environmental

MX420 CDU:

Operating Temperature: -15 to +55 °C. IEC 60, clause 4.5.2 and

4.5.4 (draft 3 rd edition)
Storage Temperature: -30 to +70 °C. IEC 945, clause 4.5.2 and

4.5.4 (draft 3 rd edition)
Humidity: IEC 945, clause 4.5.3 (draft 3 rd edition)
Vibration: IEC 945, clause 4.5.7 (draft 3 rd edition)
Solar Radiation: MIL- STD- 810E, Method 505.3, Procedure
II
Corrosion: 945, clause 4.5.10 (draft 3 rd edition)
Water Resistance: MIL- STD- 108E, Procedure 4.10. EMC: EN

Compass Safe Distance: 1.5 m. (Recommended)

MX421 Antenna:

Operating Temperature: -25 to +70 °C.
Humidity: MIL- STD- 810E, Method 507.3, Procedure

Technical Specifications

50081- 1/ 1992, EN 50082- 1/ 1992 and
55022/ 1994 class B, IEC 801- 2/ 1991, IEC
801-3/ Draft Second Edition, IEC 801- 4/
1998, IEC 945/ 1994, IEC 80/
106/ CDV/ 1995 (Draft IEC945), FTZ 171 R
32/ Aug. 1985, FTZ 171 R 45/ Jan. 1989,
FTZ 171 R 46/ Dec 1988

I. 100% R. H. for 30 days at 24 °C

Power:

MX420 CDU :

Type: DC/ DC switch mode with galvanic separa­tion
Consumption: Less than 11W (display back light on). Typi

Supply voltage: 12 or 24 volt battery: 9.6 volt dc to 32 VDC
Reverse protection: -100 volt: internal diode
Over voltage protection: +40 volt: fuse and transient voltage sup

Fuse: Internal over current / over temperature

Insulation: Supply voltage to data pins or shield: Maxi

Antenna supply: 12 VDC, maximum 500mA

cal 8W at 24 volt external supply voltage.
Typical 8.7W at 12 volt external supply volt
age

pression

fuse. Automatic resetting

mum 50 VDC

14

Antenna:

MK 421: 12 VDC, 200 mA
MK 421B: 12 VDC, 280 mA

MX420 CDU Inputs and Outputs:

The input and output circuits of the serial interfaces meet the requirements of:

• IEC 61162-1 including the requirements of ITU-T V.11.

• NMEA 0183 version 1.5, 2.0, 2.1, 2.2 & 2.3

NMEA talker (all outputs):

Levels: Maximum ±6 volt, minimum ±2 volt, A out

Current: Minimum 15mA
Protection: -1 volt to +6 volt, output relative to shield,

NMEA listeners (all inputs):

Insulation: Opto coupler. Maximum ±50 volt, input

Impedance: Minimum 500 Ohms, A- in relative to B- in
Threshold: Maximum 2 volt and 2 mA

Protection: ±15 volt, A- in relative to B- in, ±50 volt,

MX420 Installation and Service ManualTechnical Specifications

relative to B out

±50 volt, output relative to external power
lines

relative to shield or power supply lines

input relative to shield or
power

15

MX420 Installation and Service Manual

MOB/ Event input

Insulation: Maximum ±50 volt, input relative to power

Impedance: 3.5 kOhm input relative to Reference GND
Pull-up: 15 kOhm to internal 12 volt
Threshold: Positive going maximum 2.3 volt, input

Protection: ±25 volt, input relative to shield

Frequency: Triggered with 50 mS bounce control
Pulse width: Minimum 100 mS

Cable B Pins: Pin 6 (normally open) to Pin 1 (GND)

Alarm output

Signal levels: When not in Alarm state, or after

Cable A Pins: Pin 18 (N.O. contact to GND)

Antenna voltage output (Cable A)

DC voltage: 12 VDC, +1.0 VDC loaded; (11.5 VDC

DC current: Maximum 500 mA at 12.0 volt DC

Technical Specifications

supply lines

relative to Reference GND Negative going
minimum 0.6 volt, input relative to
Reference GND Hysteresis minimum 0.6
volt

±50 volt, input relative to external
power lines

acknowledged alarm: Normally Open
When in Alarm On state: Closed to Ref.
GND

nominal unloaded)

1 PPS Output (optional)

Output : 1 PPS + 50 ns RMS
Signal levels: 0-12 Volt
Pulse width: 250 mS.

Rise Time: 25 nS.

16

MX420 Installation and Service Manual

SECTION 3

MECHANICAL AND INSTALLATION DRAWINGS

17

MX420 Installation and Service Manual

18

AUXA

266 mm

A

271 mm

MX420 Installation and Service Manual

WPT

RTE

NAV

TIDE

PLOT

MX420_DIM.cdr

LL DIMENSIO NS IN MM.

Figure 3.1 MX420 Display Console Dimensions

RUBBER SEAL

(Front View)

POS

GPS

IS

CFG

E

C

139 mm

145 mm

19

MX420 Installation and Service Manual

53mm

28.5mm

81.5mm

100 mm

Cable Dressing Space

13.25mm

118.5mm

Mounting
Bracket

13.25mm

50mm

147.5mm

10mm

6137-01B.400

7mm

251mm

Rear Panel

10mm

Figure 3.2 MX420 Display Console Dimensions

(Top and Side View)

20

24.5mm

28.5mm

53mm

AUXA

298 mm

MX420 Installation and Service Manual

RTE

NAV

PLOT

PLOT

POS

PO

E

E

S

RTE

TIDE

TIDE

GPS

G

CFG

CFG

WPTNAV

WPT

AUX

IS

AI S

PS

C

C

147.5 mm

6290- 11A.400

Figure 3.3 Gimbal Mount

21

MX420 Installation and Service Manual

MX 4 2 0

Flush Mount

Hole Size Requirements

251mm

119mm

REAR PANEL

Mi ni mum Bend Radius

50 mm

Mi n i mu m

Free Space

100 mm

Max i mu

Figure 3.4 Standard Flush Mount and Cable Clearance

22

9 mm

MX420 Installation and Service Manual

MX 420

Flush Mount Fr ame

Hole Si ze Requi rements

271mm

FRONT PANEL

119mm

Figure 3.5 Optional Flush Mount Frame Installation

23

MX420 Installation and Service Manual

89 mm

20 mm

182 mm

8-Pin Connector

1 in.- 14 TPI

1 IN. DIA. MOUNTING POLE

(USER SUPPLIED)

Figure 3.6 MX421/B Antenna Dimensions and Mount Specifications

24

MX420 Installation and Service Manual

SECTION 4

ELECTRICAL INSTALLATION DRAWINGS

25

MX420 Installation and Service Manual27MX420 Installation and Service Manual

26

or

MX 421

MX 421B

NMEA1

NMEA3/Ant. I/O)

NMEA2 (RS-232/RS-422)

Switched 12 VDC

EXT. ALARM

12-32 VDC Power Input

Cable A

Terminal Block

(User Supplied)

Figure 4.1 MX420/2 Basic System Configuration

MX 420/2

MX 422 Professional D GPS NavigatorMX 422 Professional D GPS Navigator

MX420 Installation and Service Manual

To NMEA Compatible Equipment

Port 1 (RS-422)

From NMEA Compatible Equipment

RED

MX421/ B

GRN

ORG

Port 2 (RS-2 32)

To NMEA Compatible Equipment

Port 2 (RS-42 2)

From N MEA Compat ible Equipm ent

BRN

BLU

Ref. To Pin 3 (Neg.)

Exte rnal Alar m Output

Negative GND.

+12~ 32 VDC P ower

BLK

Fuse

2 Amp.

RED

Te r m i n al Bl oc k

(User Supplied)

[NMEA3/GPS In (B)]

[NMEA3/GPS Out (B)]

[NMEA3/GPS In (A) from Ant.]

[NMEA3/GPS Out (A) fr om Ant.]

RED [Pwr In +12~32 Vdc]

RED/WHT [+12 V Out to Mx421]

BRN [NMEA1 In (A)]

BRN/WHT [NMEA1 In (B)]

PRPL [N MEA1 O ut (A )]

YEL

YEL/BLK

ORG

ORG/WHT

PRPL/WHT [NMEA1 Out (B)]

BLK

Figure 4.2 MX420/2 Basic Wiring Diagram

BLU [NMEA2 Out (A)]

BLU/WHT [NMEA2 Out (B)]

GRN [NMEA2 In (A)]

GRN/WHT [NMEA2 In (B)]

Shield [ Gnd. to MX421]

BLK [Pwr In (-)]

BLK/WHT [ ALARMout]

GRY [RS-232 TXD]

GRY/BLK [Not Used]

Cable A

Mx420 /2

(18-Pin)

Connector (A)

4

1

5

2

16

8

679

10

11

1213141518

3

17

NC

MX 422 Professional DGPS Navigator

28

MX420 Installation and Service Manual

Terminal Block (3x)
(User Supplied)

MX 421

or

MX 421B

MX 420/8

MX 422 Professional DGPS Navigator

Cable A

NMEA1

NMEA2
NMEA3/GPS

EXT. ALARM

12-32 VDC

DIGITAL In(1)
DIGITAL In(2)

Cable B

*NMEA4 (TX only)

NMEA5
NMEA6

1 PPS

EXT. MOB

Cable C

NMEA7
NMEA8
NMEA9
NMEA10

* NMEA4 fixed at 4800 Baud Only

Figure 4.3 MX420/8 System Configuration

(RS-232/RS-422)

29

MX420 Installation and Service Manual

Connector (A)
(18-Pin

) Female

Shield (G ND)

1
2

RED [Pwr In +12~32 Vdc]
RED/WHT [+12 V Out to Mx421]

16

BRN [NMEA1 In (A)]

4

BRN/WHT [N MEA1 In (B)]

5
6

PRPL [NMEA1 Out (A)]
PRPL/WH T [NMEA1 Out (B)]

7
8

ORG

[NMEA3/GPS In (A) from Ant.]

ORG/WHT

[NMEA3/GPS In (B)]

[NMEA3/GPS Out (A) from Ant.]

YEL

[NMEA3/ GPS Out (B) ]

YEL/BLK

GRN [NMEA2 In (A)]
GRN/WHT [NMEA2 In (B)]

BLU [NMEA2 Out (A)]
BLU/WHT [NMEA2 Out (B)]

BLK [Pwr In (-)]
BLK/WHT [ ALARMout]

Shield [ Gnd. to MX421]
GRY [RS-232 TXD]
GRY/BLK [Not Used]

Shield (GND )

(Digital In 2)

BLK
BLK/WHT

(Digital In 1)

BRN

[NMEA4 / Beac on In (A)]

[NMEA4 / Be acon In (B)]

BRN/WHT

RED (MOB/Event)

RED/WHT (Not Used)

ORG (NMEA5 In - A)
ORG/WHT (NMEA5 In - B)

YEL (NMEA5 Out - A)
YEL/BLK (NMEA5 Out - B)

GRN (NMEA 6 In - A)
GRN/WHT (NMEA6 In-B)

BLU (NMEA6 O ut - A)
BLU/WHT (NMEA6 Out -B)

PRPL/WHT (

Not Used)

PRPL (

Not Used)

GRY (1 PPS +)

GRY/B LK (1PPS -)

Shield (G ND)

BLK [NMEA8 In (A)]

BLK/WHT [NMEA8 In (B)]

BRN [NMEA9 In (A)]

BRN/WHT [NMEA9 In (B)]

RED [NMEA9 Out (A)]

RED/WHT [NMEA9 Out (B)]

ORG [NMEA 10 In (A)]

ORG/WH T [(NMEA1 0 In

YEL [NMEA10 Out ( A)]

YEL/BLK [NMEA10 Out (B)]

GRN [NMEA7 In (A)]

GRN/WHT [NMEA7 In (B)]

BLU [NMEA7 Out (A)]

BLU/WHT [NMEA7 Out (B)]

PRPL [NMEA8 Out (A)]

PRPL/WHT [NMEA8 Out (B)]

GRY (not used)

GRY/BLK (not connected)

(B)]

MX420/8

MX 422 Professi on al DGPS N avigat orMX 422 Professi on al DGPS N avigat or

Cable A

Cable B

Cable C

9

10

11
12
13
14
15

3

18

17

N.C.

Connector B
(Male)

1
2
3
4
5
6

N.C.

8

9
10
11
12
13
14

15

7

16

17
18

Connector C
(Male)

1

2

3

4

5
6
7

8

9

10
11
12
13
14
15
16
17
18
N.C.

Terminal Block

(User Supplied)

MX421/B
Antenna

2 Amp.

Fuse

RED

RED

GRN

ORG
BRN
BLU

BLK

WHT
YEL

*

NMEA4 Fixed at 4800 Baud Rate

PORT1 (RS-422)
NMEA equi pment
or Dual Control

Power Input

+

-

12~32 VDC

Log Input Pulses

Figure 4.4 MX420/8 Wiring Diagram

30

MX420 Installation and Service Manual

(Slave)

MX420/2

MX 422 Professional DGPS Navigator

NMEA1 IN

Cable (A)

NMEA1 OUT

Cable (A)

NMEA1 IN

NMEA1 OUT

MX421/B

MX 422 Professional DGPS Navigator

(Master)

MX420/8

Figure 4.5 MX420/BR Dual Control System

31

MX420 Installation and Service Manual

5

7

4

1

2

16

(18-Pin)

Connector (A)

BRN [NMEA1 In (A)]

BRN/WHT [NMEA1 In (B)]

RED [Pwr In +12~ 32 Vdc]

RED/WHT [+12 V Out to Mx421]

Te rm i na l B lo c k

(User Supplied

RED

RED

MX421/ B

RED

9

8

6

1011121314

[NMEA3 / GPS In (B)]

[NMEA3 / GPS Out (B)]

PRPL [NMEA1 Out (A)]

PRPL/WHT [NMEA1 Out (B)]

[NMEA3 / GPS In (A) from Ant.]

[NMEA3 / GPS Out (A) from Ant.]

YEL/BLK

ORG

ORG/ WHT

YEL

BRN

BLU

GRN

ORG

3

15

17

18

NC

(Slave)

MX 422 Professional DGPS Navigator

Mx420/2

GRY [RS-232 TXD]

GRY/BLK [Not Used]

BLK [Pwr In (-)]

GRN [NMEA2 In (A)]

BLK/WHT [ ALARMout]

GRN/WHT [NMEA2 In (B)]

BLU [NMEA2 Out (A)]

BLU/WHT [NMEA2 Out (B)]

Ref to Pin3 (Neg.)

BLK

Fuse

2 Amp.

To Cable B

See Fig. 4.4

Power

To Negati ve GND.

+12~32 VDC

BLK

BLK

Fuse

2 Amp.

Terminal Block

(User Supplied)

Ref to Pin3 (Neg.)

[NMEA3 / GPS In (B)]

[NMEA3 / GPS Out (B)]

[NMEA3 / GPS In (A) from Ant.]

[NMEA3 / GPS Out (A) from Ant.]

RED [Pwr In +12~32 Vdc]

RED/WHT [+12 V O ut to Mx421]

BRN [NMEA1 In (A)]

BRN/WHT [NMEA 1 In (B)]

(18-Pin)

Connector (A)

5

4

1

6

2

16

YEL

YEL/BLK

GRN [NMEA 2 In (A)]

ORG

PRPL [NMEA1 Out (A)]

PRPL/WHT [NMEA 1 Out (B)]

7

8

GRN/W HT [NMEA2 In (B )]

ORG/WHT

9

11

10

121314

Shield [GND to Mx421]

BLU [ NMEA2 Out (A)]

BLU/WHT [NMEA2 Out (B)]

BLK [Pwr In (-)]

BLK/WHT [ ALARMout]

GRY [RS-232 TXD]

GRY/BLK [Not Used]

3

15

17

18

NC

Note: For details on Cables B and C

refer to Figure 4.4.

(Master)

MX420/8

MX 422 Professional DGPS Navigator

Figure 4.6 MX420/BR Dual Control Wiring Diagram

32

MX420 Installation and Service Manual

(Slave)

B

/
1
2
4
X

M

MX420/8

MX 422 Professional DGPS Navigator

NMEA1 IN

Cable (A)

NMEA1 OUT

Cable (A)

NMEA1 IN

NMEA1 OUT

B

/
1
2
4
X

M

MX 422 Prof essional DGPS Navigat or

(Master)

MX420/8

Figure 4.7 MX420/BRIM Dual Station Integrity Monitor System

33

MX420 Installation and Service Manual

1

2164

(18-Pin)

Connector (A)

BRN [NMEA1 In (A)]

RED [Pwr In +12~32 Vdc]

RED/WHT [+12 V Out to Mx421]

Terminal Block

(User Supplied

RED

RED

MX421B M X421B

RED

9

8

7

5

6

BRN/WHT [NMEA1 In ( B)]

PRPL [ NMEA1 Out (A)]

11

10

[NMEA3 / GPS In (B)]

[NMEA3 / GPS Out (B)]

PRPL/WHT [NMEA1 Out (B)]

[NMEA3 / GPS In (A) from Ant.]

[NMEA3 / GPS Out (A) from Ant.]

YEL/BLK

ORG/WHT

ORG

YEL

BRN

BLU

GRN

ORG

3

15

13

18

14

12

GRN [NMEA2 I n (A)]

GRN/WHT [NMEA2 In (B)]

BLU [NMEA2 Out (A)]

17

NC

MX 422 Professional DGPS Naviga t or

(Slave)

MX420/8

GRY [RS-232 TXD]

GRY/BLK [Not Used]

BLK [Pwr In (- )]

BLK/W HT[A LARM out]

Shield [ Gnd. to MX421]

BLU/WHT [NMEA2 O ut (B)]

Note: For details on Cables B & C,

refer to F igure 4.4

Fuse

2 Amp.

Power

To Negative GND.

+12~32 V DC

Fuse

2 Amp.

BLK

BLK

BLK

Port2 Ref. To P3 (Neg.)

To C abl e B

(See Fig. 4 .4)

Terminal Block

(User Su pplied)

Port2 Ref. To P3 (Neg.)

[NMEA3 / GPS In (B)]

[NMEA3 / GPS Out (B)]

[NMEA3 / G PS In (A) from Ant.]

[NMEA3 / GPS Out (A) from Ant.]

RED [Pwr In +1 2~32 Vdc]

RED/WHT [ +12 V O ut to Mx42 1]

BRN [NMEA1 In (A)]

BRN/WHT [NMEA1 In (B)]

(18-Pin)

1

2164

5

Connector (A)

6

PRPL [NMEA1 Out (A)]

YEL

YEL/BLK

ORG

ORG/WHT

GRN [NMEA2 In (A)]

GRN/WHT [N MEA2 In (B)]

BLU [NMEA2 Out (A)]

BLU/WHT [NMEA2 Out (B)]

BLK [Pwr In (-)]

PRPL/WH T [NMEA1 Out (B)]

9

8

7

11

10

12

BLK/WHT [ALARMout]

Shield [ Gnd. to Mx421]

GRY [RS-232 TXD]

3

15

13

18

14

17

GRY/BLK [Not Used]

NC

Note: For details on Cables B & C,

refer to Fig ure 4.4

(Master)

MX420/8

MX 422 Professional DGPS Navigat or

Figure 4.8 MX420/BRIM Dual Station Integrity Monitor Interface Diagram

34

r

)

1

2

4

6

5

10

11

9

14

13

15

16

18

17

Conn. A Pin Assignments

(Front View)

18-Pin Female Connec to

3

78

12

MX420 Installation and Service Manual

Cable A

18-Pin (Female
Connector

1

2

16

4
5
6
7

8
9

10

11

12

13
14
15

3

18

17

NC

2.0 meters

Cable A

RED [PWR In +12~32 Vdc]
RED/WHT [+12 V Out to Ant.]

BRN [NMEA1 In (A)]
BRN/WHT [NMEA1 In (B)]

PRPL [NMEA1 Out (A)]
PRPL/WHT [NMEA1 Out (B)]

ORG [NMEA3 / GPS In (A) from Ant.]
ORG/WHT [NMEA3 / GPS In (B)]

YEL [NMEA3 / GPS Ou t (A) to Ant.]
YEL/BLK [NMEA3 / GPS Our (B)]

GRN [NMEA2 In (A)]
GRN/WHT [N MEA2 In (B) ]

BLU [NMEA2 Out (A)]
BLU/WHT [NMEA2 Out (B) ]

BLK [PWR In (-)]
BLK/WHT [ALARMout}

SHIELD [ GND. To Mx421]

GRY [RS-232 TxD (NMEA2 Out)]
GRY/BLK [Not Used]

}

Brown

}

}

Green

}

Blue

}

Black

}

Red

Purple

}
}

Gray

}

Orange

Ye ll ow

Figure 4.9 Cable (A) Wiring Configuration

35

MX420 Installation and Service Manual

)

Cable B

18-Pin Male Connector

18-Pin (Male
Connector

1

2

3
4

5

6

NC

8

9
10

11

12

13
14

15

7

16

17
18

1

2

5

6

4

10 9

14

17

18

(Front View)

87

13

16

11

15

Conn. B Pin Assignments

3

12

2.0 meters

Cable B

Shield ( GND)

BLK [DIGITAL2 In (Log )]
BLK/WHT [DIGI TAL1 In]

RED (EXT. MOB/Event) Ref. To Pwr. GND.
RED/WHT (Not connecte d)

YEL [NMEA5 Out ( A)]
YEL/BLK [ NMEA5 Out (B)]

GRN [NMEA 6 In (A)]
GRN/WHT [NMEA6 In (B)]

BLU [NMEA6 Out (A)]
BLU/WHT [NMEA6 Out (B)]

PRPL/WHT (Not Us ed)
PRPL (Not Used)

GRY (Optional 1 PPS +)
GRY/BLK (Optional 1PPS -)

}

}

}

}

}

}

}

Black

Orange

Yel l ow

Green

Blue

Purple

Gray

}

Brown

Red

}

Figure 4.10 Cable (B) Wiring Configuration (Only on MX420/8)

36

)

1

2

6

5

15

10

14

18

(Front View)

4

98

13

16

17

11

Conn. C Pin Assignments

Cable C

18-Pin Male Connector

18-Pin (Male
Connector

3

7

12

MX420 Installation and Service Manual

2.0 meters

Cable C

Shield (GND)

BLK [NME A8 In (A) ]
BLK/WHT [NMEA8 In (B)]

BRN [N MEA9 In (A) ]
BRN/WHT [N MEA9 In (B)]

RED [NMEA9 Out (A)]
RED/WHT [NMEA9 Out (B)]

ORG [NMEA10 In (A)]
ORG/WHT [(NMEA10 In (B)]

YEL [NMEA10 Out (A)]
YEL/BLK [NMEA10 Out (B)]

GRN [NMEA7 In (A)]
GRN/WHT [NMEA7 In (B)]

BLU [N MEA7 Out (A)]
BLU/WHT [N MEA7 Out (B)]

PRPL [NMEA8 Out (A)]
PRPL/WHT [NMEA8 Out (B)]

GRY (not used)
GRY/BLK (not connected)

10
11

12

13

16

18
NC

1

2

3

4
5

6

7

8

9

14
15

17

}

}
}
}

}

}

}

}
}

Black

Brown

Red

Orange

Ye ll ow

Green

Blue

Purple

Gray

Figure 4.11 Cable (C) Wiring Configuration (Only on MX420/8)

37

MX420 Installation and Service Manual

Figure 4.12 MX420/2 Rear Panel Connector

Figure 4.13 MX420/8 Rear Panel Connectors

38

*White (Beacon Status Out +.)

*Yellow (Beacon Status Out -. )

Green (GPS Out+)

Orange(GPS Out-)

MX421 (8-Pin Conn.)

Wire

Pin#

White

8*

Yel l o w

7*

Green

6

Orange

5

Brown

4

Blue

3

Red

2

Black (GND)

1

Note:
7* Connect to Cable B (Brown/White) for MX420/8 or MX420/AIS models

8* Connect to Cable B (Brown) For MX420/8 or MX420/AIS models.

MX420 Installation and Service Manual

1

7

6

8

5

4

MX421 (8 Pin Conn.)

Signal
Beacon Status Out +

Beacon Status Out ­ GPS Out +
GPS Out ­ LPM IN+
LPM IN-

+12 VDC

.

Black ( GND)

Red (+12 VDC in)

2

3

Blue (LPM In -)
Brown (LPM In +)

MX420/2 or MK12

(Not Connected)

Cable A (Orange)
Cable A (Orange/White)
Cable A (Yellow)
Cable A (Yellow/Black)
Cable A (Red/White)
Cable A (Pin 1 Shield -GND)

Figure 4.14 MX421(8-Pin) GPS Antenna Wiring Diagram

39

MX420 Installation and Service Manual

***Purple/Gray (1PPS -)

***Purple (1PPS +)

*White (Beacon Out+)

*Yellow (Beacon Out-)

Green (GPS Out+)

1

10

2

9

8

Mx421-10 (10 Pin Conn.)

3

4

7

5

6

Black (GND)
Red (+12 VDC in)

Blue (LPM In -)

Brown (LPM In +)

Orange(GPS Out-)

MX421 -10 (GPS Only)

Wire

Pin#

10***

9***
8*
7*
6
5
4
3
2
1

* RTCM connection to MX421-10 (GPS only) Antenna model
** Not available in MX420/2 or MK12 CDU models
*** Not connected in MX420/2 or MK12 models

Signal

Purple/Gray 1PPS(-)

Purple 1PPS(+)

W

hite

RTCM In +

Yellow

RTCM In -

Green

GPS Out +

Orange

GPS Out -

Brown

LPM IN+
Blue
Red
Black

LPM IN-

+12 VDC

GND.

Mx420/8

Cable B (GrayBlack)**
Cable B (Gray)**

Ext. Beacon Corr. +
Ext. Beacon Corr. ­Cable A (Orange)
Cable A (Orange/White)
Cable A (Yellow)
Cable A (Yellow/Black)
Cable A ( Red/White)
Cable A (Pin 1 Shield-GND)

Figure 4.15 MX421-10 (10-Pin) GPS Only Antenna Wiring Diagram

40

***Purple/Gray (1PPS -)

***Purple (1PPS +)

*White (Beacon Status Out+)

*Yellow (Beacon Status Out-)

Green (GPS Out+)

MX420 Installation and Service Manual

1

10

2

9

8

Mx421-10 (10 Pin Con n.)

3

4

7

5

6

Black(GND)
Red (+12 VDC in)

Blue (LPM In -)

Brown (LPM In +)

Orange(GPS Out-)

MX421B-10 (DGPS)

Wire

Pin#

10***

9***
8*
7*

6
5
4
3
2
1

*Not connected in MX421 (GPS only) Antenna model
**Not connected in MX420/2 or Mk12 CDU models
***Pins 9 &10 avail able only on MX421-10 antenna model

Signal

Purple/Gray 1PPS(-)
Purple 1PPS(+)

W

hite

Beacon Status Out +
Beacon Status Out -

Yellow
Green
Orange
Brown
Blue
R

ed

Black

PS Out +

G
GPS Out ­ LPM IN+
LPM IN-

+12 VDC

GND.

Mx420/8 or MX420/AIS

Cable B (GrayBlack)**
Cable B (Gray)**

Cable B (Brown)**
Cable B (Brown/Whit e)**
Cable A (Orange)
Cable A (Orange/White)
Cable A (Yellow)
Cable A (Yellow/Black)
Cable A (Red/White)
Cable A (Pin 1 Shield -GND)

Figure 4.16 MX421B-10 (10-Pin) DGPS Antenna Wiring Diagram

41

MX420 Installation and Service Manual

42

A

MX421

A

A

A

A

A

Smart GPS
Antenna

MX420/AIS

GPS Ant.

VHF Ant.

GPS

VHF

NMEA1

(Ext.

GPS)

NMEA2

NMEA3

(Mx421)

*

A

NMEA4

NMEA5
(Mx423)

(Mx421)

* Auxiliary GPS receiver connectio n using NMEA 0183 interface.
** RTCM - differential correction from a beacon receiver.

NMEA6

(Long

Range)

CB

NME

NME

7

(ECDIS/

(Gyro)

)

ARP

8

NME

(Pilot

Laptop)

CONFIG

9

NME

(Speed

Log)

PSP

10

UX

RTCM**

MX423-AIS

Transponder

Figure 4.17 MX420/AIS CDU & MX423 (SAAB) Transponder System Block Diagram

ABA

ABA

MX420/AIS

MX 422 Professional DGPS Navigator

Cable A

Cable B

Connector (A)

Connector (B)

Connecto r (C)

Cable C

(18-P in)

(18-Pin)

(18-Pin)

Shield (GND)

RED [Pwr I n +12~32 Vdc]
RED/WHT [+12 V O ut to Mx421]

BRN [NMEA1 In (A)]
BRN/WHT [NMEA1 In (B)]

PRPL [NMEA1 Out (A)]
PRPL/WHT [NMEA 1 Out (B)]

ORG [N MEA3 / GPS In (A )]
ORG/WHT [NMEA3 / GPS In (B)]

YEL [NMEA3 / GPS Out (A)]
YEL/BLK [NMEA3 / GPS Out (B)]

GRN [NMEA2 In (A)]
GRN/WHT [NMEA2 In (B)]

BLU [NMEA2 Out (A)]
BLU/WHT [NMEA2 Out (B)]

BLK [Pwr In (-)]
BLK/WHT [ ALARM Out]

Shield [Gnd. to MX421]
GRY [RS-232 TXD]

GRY/BLK [Not Connected]

Shield (G ND)

BLK [Digital In 2]
BLK/WHT [Digital In 1]

BRN [NMEA4 / Beacon In (A)]
BRN/WHT [NMEA4 / Beac on In (B)]

RED [MOB / Event]
RED/WHT [Not Connected]

ORG [NMEA5 In (A)]
ORG/WH T [NM EA5 I n (B)]

YEL [NMEA5 Out (A)]
YEL/BLK [NMEA5 Out (B) ]

GRN [NMEA6 In (A)]
GRN/WH T [NMEA6 In ( B)]

BLU [NMEA6 O ut (A)]
BLU/WHT [NMEA6 Out (B)]

PRPL/WHT [Not Used]
PRPL [Not Used]

GRY [1 PPS +]
GRY/BLK [1PPS -]

Shield (G ND)

BLK [NMEA8 In (A)]
BLK/WHT [NMEA8 In ( B)]

BRN [NMEA9 In (A)]
BRN/WHT [NMEA9 In (B )]

RED [NMEA9 Out (A)]
RED/W HT [NMEA 9 Out (B )]

ORG [NMEA10 In (A)]
ORG/WH T [(NM EA10 In (B )]

YEL [NMEA10 Out (A)]
YEL/BLK [NMEA10 Out (B)]

GRN [NMEA7 In (A)]
GRN/WH T [NMEA7 In ( B)]

BLU [NMEA7 Out (A)]
BLU/WHT [NMEA7 Out (B)]

PRPL [NMEA8 Out (A)]
PRPL/WHT [N MEA8 Out (B)]

GRY [Not Used]
GRY/BLK [Not Connected]

Terminal

Blocks

RED

RED

GRN
ORG
BRN
BLU

BLK

BLK

WHT

YEL

*PURPLE

*PURPLE/ GREY

*Note: Optional 1PPS
connection from
Mx421 antenna.

Optional MX421B or
3rd Party Smart GPS
Antenna

Ext.
Alarm Relay

2 Amp.

Fuse

+

Power Supply

12~32 VDC

-

N.O.

C

N.C.

To a Battery Backed-Up

Alarm Power Supply

-

+

ORG
ORG/WHT

YEL
YEL/BLK

4 Amp.

Fuse

+

-

Power supply

24 VDC

GRN
GRN/WHT

GRN
GRN/WHT

BLU
BLU/WHT

BLK
BLK/WHT

BRN
BRN/WHT

RED
RED/WHT

ORG
ORG/WHT

GRN
GRN/WHT

BLU
BLU/WHT

Te r mi n a l

Block

CONFIG connector:
9 pole D-SUB M

N.O.

C

N.C.

A
B

Alarm Unit

Tx

Sensor

(RS-422)

Long Range Comm.

Tx

I/O Port

Rx

B

A

Tx

B

A

Tx

B
A

Rx

B

A

Tx

B

Tx

Rx

B

(RS-422)

Sensor

High Speed Equipment

I/O Port

(RS-422)

Sensor

(RS-422)

High Speed Equipment

I/O Port

(RS-422)

(RS-422)

Mx423

AIS Transponder

CONFIG (RS-2 32)

VHF ANT

GPS ANT

PSP / AUX (RS-422)

POWER

MX423-AIS Shipborne Class A Transponder System

Connected Equipment

Default port 2
setting = Ext GPS

Default port 6
setting = Long Range Eq.

Default

port 8

= Gyro

setting

Default

port 9

= PILOT

setting

Default

port 10

= Speed Log

setting

Default

port 7

= ECDIS

setting

Figure 4.18 MX420/AIS CDU & MX423 (SAAB) Transponder System Wiring Diagram

EXT.
GPS

GPS

S1

LOG

ANT.

VHF

ANT.

LAN

GPS

VHF

PP

ATLAS

PILOT

ECDIS/

PC

ARPA

MX421B-10
SMART DGPS
ANTENNA

(NOT REQUIRED FOR MKD).

MX420/AIS

OR

MX420/MKD

GPS OUT (GLL)

Non-ATLAS

ECDIS/

ARPA

SPD LOG

(PULSES)

S3 (GLL,DTM,VTG)

LONG

RNG.

MX531 AIS

TRANSPONDER

PDP

LR

S2

SPEED

GYRO

& ROT

(NMEA)

Figure 4.19 MX420/AIS/MKD CDU & MX531 (ATLAS) Transponder Block Diagram

EXT.

ALARM

A

/

ABA

MX420/AIS

A

V

ABA

A

y

y

g

MX 422 Professional DGPS Navigator

Cable A

Cabl e B

Connector (A)

Connector (B)

Connector (C)

Cable C

(18-Pin)

(18-Pin)

(18 -Pin )

Shield (GND)

RED [Pwr In +12~32 Vdc]
RED/WHT [+12 V Ou t to Mx421]

BRN [NMEA1 In (A)]
BR N/W HT [N MEA 1 In ( B) ]

PRPL [NMEA1 Out ( A)]
PRPL/WHT [NMEA1 Out (B )]

ORG [NMEA3 / GPS In (A)]
ORG/WHT [NMEA3 / GPS In (B)]

YEL [NMEA3 / GPS Out ( A)]
YEL/BLK [NMEA3 / GPS Out (B)]

GRN [NMEA2 I n (A)]
GRN/WHT [NMEA2 In (B)]

BLU [N MEA2 Out (A)]
BLU/WHT [NMEA2 Out (B)]

BLK [Pwr In (-)]
BLK/WHT [ ALARM Out]

Shield [Gnd. to MX421]
GRY [RS-232 TXD]

GRY/BLK [Not Connected]

Shield (GND)

BLK [Digital In 2]
BLK/WHT [Digital In 1]

BRN [NMEA4 / Beacon In (A)]
BRN/WHT [NMEA4 / Beacon In (B)]

RED [MOB / Event]
RED/WHT [Not Connected]

ORG [NMEA5 In (A)]
ORG/WHT [NMEA5 In (B)]

YEL [NMEA5 Out (A)]
YEL/BLK [NMEA5 Out (B)]

GRN [NMEA6 I n (A)]
GRN/WHT [NMEA6 In (B)]

BLU [NMEA 6 Out (A)]
BLU/WHT [NMEA6 Out (B)]

PRPL/WHT [ Not Used]
PRPL [Not Used]

GRY [1 PPS +]
GRY/BLK [1PPS -]

Shield (GND)

BLK [NMEA8 In (A)]
BLK/WHT [NMEA8 In (B)]

BRN [NMEA9 In (A)]
BRN/WHT [NMEA9 In (B)]

RED [NMEA9 Out (A)]
RED/W HT [NMEA9 Out (B )]

ORG [NMEA10 In (A)]
ORG/ WHT [( NMEA 10 In (B )]

YEL [NMEA10 Out (A)]
YEL/BLK [NMEA10 Out (B)]

GRN [NMEA7 I n (A)]
GRN/WHT [NMEA7 In (B)]

BLU [N MEA7 Out (A)]
BLU/WHT [NMEA7 Out (B)]

PRPL [NMEA8 Out (A)]
PR PL /W HT [ NM EA 8 O ut (B )]

GRY [Not Used]
GRY/BLK [Not Connected]

Ter mi nal

Blocks

RED

RED

GRN
ORG
BRN
BLU

BLK

BLK

WHT
YEL

*PURPLE

*PURPLE/GREY

*Note: Optional 1PPS
connection from
Mx421 antenna.

Optional MX421B or
3rd Part y Smart G PS
Antenna

Ext.
Alarm Relay

2 Amp.

Fuse

+

Power Supply

12~32 VDC

-

N.O.

C

N.C.

To a Battery Backed-Up

larm Po wer S uppl y

-

+

GRN
GRN/ WHT

(RS-422)

GRN/WHT

BLU/WHT

GRN

BLU

Default Port 1

A

Tx

setting = Ext GPS

B

Long Range Comm.

GYRO/ROT

SPEED LOG

PILOT PC

(RS-422)

Tx

Rx

B

ECDIS

(Non-ATLAS)

MX531 TRANPONDER UNIT

GPS IN

+ -+ -

B

I

O Port

(RS-422)

(RS-422)

(RS-422)

Alarm Unit

HF

24V

GPS OUT

+ -

+ -

B

B

A

A

A

PDP OUT

PI IN

+ -+ -+ -

B

YEL

YEL/BLK

A

ORG

ORG/WHT

PDP IN

LR OUT

LR IN

+ -

B

S3 IN

+ -

B

S2 IN

+ -

B

A

A

+ -

B

GND

GND

A

PI OUT

A

S1 IN

RELAY

GND

GND

GND

+ -

1 2 3

GPS

LAN

4 Amp.

Fuse

+

-

Power supply

24 VDC

ccording to:
Power suppl
Required b
and
Electrical/Electronic navi
Eqpt. Required by SOLAS
Chapter V, Reg.12

Tx

Rx

B

A

Tx

B

A

Tx

Tx

Rx

B

A
B
A
B

N.C .

C

N.O.

1
2

3

TLAS

ECDIS/ARPA

to radio eqpt.

SOLAS Chapter IV

ation

Figure 4.20 - MX420/AIS/MKD CDU & MX531 (ATLAS) Transponder System Wiring Diagram

A

CX4

V

HF ANT

GPS ANT.

MX ANTENNA

B C

JB-50
J- BOX

(Optional)

MX535
AIS TRANSPONDER

GYRO

SPEED

GPS

PILOT PLUG

Figure 4.21 MX420/AIS/MKD CDU & MX535 (NAUTICAST) Transponder Block Diagram

ABA

Cable A

A

A

A

A

ABA

ABA

ABA

Connector (A)

(18-Pin)

Shield (GND)

RED [Pwr In +12~32 Vdc]
RED/WHT [+12 V Out to Mx421]

BRN [NMEA1 In (A)]
BRN/WHT [NMEA1 In (B)]

PRPL [NMEA1 Out (A)]
PRPL/WHT [NMEA1 Out (B)]

ORG [NMEA3 / GPS In (A)]
ORG/WHT [NMEA3 / GPS In (B)]

YEL [NMEA3 / GPS Out (A)]
YEL/BLK [NMEA3 / GPS Out (B)]

GRN [NMEA 2 I n (A)]
GRN/WHT [NMEA2 In (B)]

BLU [NMEA2 Out (A)]
BLU/ WHT [NM EA2 Ou t (B)]

BLK [Pwr In (-)]
BLK/WHT [ ALARM Out]

Shield [G nd. to MX421]
GRY [RS-232 TXD]

GRY/BLK [Not Connected]

Ter mi na l

Blocks

RED

BLK

RED

GRN
ORG
BRN
BLU

BLK

VHF

GPS

MX-M ARINE

Smart G PS

Antenna

N.O.

C

N.C.

Ext.
Alarm Re lay

Ext. Alarm Output

(both units)
See 3.3.2.6

N.O.

C

To a Battery Backed-Up

larm Po wer S uppl y

-

+

10_1

10_2

CH

CH

MX535 TRANPONDER UNIT

OUT

OUT

IN
9

8

6_CANL

6_CANH

6_Vin

6_gnd

Spa re _OU T

CH

CH

CH

CH

- +

- +

A

CH 9

Spare_IN

Spare_GND

GND

- +- +

B

BAB

A

A

8

CH

CH IN

CH

- +

B

B

A

- +

A

GND

GND

- +

B

A

OUT
5

CH

B

IN

CH5

- + -

B

A

OUT

IN
4

CH

CH4

GND

- +- +

B

B

A

A

IN

IN
3

2

CH

CH

GND

- +

- +

B

A

CH1 IN

- +

GND

GND

B

B

A

A

24V

GND

GND

GND

MX420/AIS

MX 422 Professional DGPS Navigator

Cable B

Connector (B)

Connector (C)

Cable C

(18-Pin)

(18-Pin)

Shield (GND)

BLK [Digital In 2]
BLK/WHT [Digital In 1]

BRN [NMEA4 / Beacon In (A)]
BRN/WHT [NMEA4 / Beacon In (B)]

RED [MOB / Event]
RED/WHT [Not Connected]

ORG [NMEA5 In (A)]
ORG/ WHT [N MEA5 In ( B)]

YEL [NMEA5 Out (A)]
YEL/BLK [NMEA5 Out (B)]

GRN [NMEA 6 I n (A)]
GRN/WHT [NMEA6 In (B)]

BLU [NMEA6 Out (A)]
BLU/WHT [NMEA6 Out (B)]

PRPL/WHT [Not Us ed]
PRPL [Not Used]

GRY [1 PPS +]
GRY/BLK [1PPS -]

Shield (GND)

BLK [NMEA8 In (A)]
BLK/WHT [NMEA8 In (B)]

BRN [NMEA9 In (A)]
BRN/WHT [NMEA9 In (B)]

RED [NMEA9 Out (A)]
RED/WHT [N MEA9 Ou t (B)]

ORG [NMEA10 In (A)]
ORG/ WHT [( NMEA 10 In (B)]

YEL [NMEA10 Out (A)]
YEL/BL K [NMEA10 Ou t (B)]

GRN [NMEA 7 I n (A)]
GRN/WHT [NMEA7 In (B)]

BLU [NMEA7 Out (A)]
BLU/ WHT [NM EA7 Ou t (B)]

PRPL [NMEA8 Out (A)]
PRP L/WHT [N MEA8 Ou t (B)]

GRY [Not Used]
GRY/BLK [Not Connected]

WHT
YEL

*PURPLE

*PURPLE/GREY

*Note: Optional 1PPS
connection from
Mx421 antenna.

2 Amp.

Fuse

+

Power Supply

12~32 VDC

-

GRN
GRN/W HT

(RS-422)

BLU/WHT

BLU

Default Port 1

A

Tx

setting = Ext GPS

B

Long Range

GYRO

(HDT, ROT)

SPEED LOG , ROT,
HEADING

(VBW)

(HDT)

ECDIS Listener

Rx

B

(Non-MX535)

+

Power supp ly

24 VDC

ccording to:
Power supply to radio eqpt.
Required by SOLAS Chapter IV
and
Electr ical /Electronic navi gation
Eqpt. Required by SOLAS
Chapter V, Reg.12

Tx

Rx

B

Tx

B

A

Tx

Tx

Rx

B

B

0 V

Tx

B

Tx

Rx

B

Figure 4.22 - MX420/AIS/MKD CDU & MX535 (NAUTICAST) Transponder System Wiring Diagram

VHF

V

ANT.

GPS

ANT.

Remote Sensor Pwr Port

(3A Maximum)

(Male)

N-Type

N-Type

(Female)

1m ± 30mm

TNC

(Male)

TNC

(Femal e)

RG58 Halogenfree

Cable gland

IP67 (EN60529)

Ter m i n al (B )

(24VDC Output Only)

(Output Only)

MX421

OR

OR

MX525

MX423

MX531

MX575

OR

SLA

E UNIT

AIS TRANSPONDER

SMART DGPS ANTENNA

(Refer to the Mx420 Installation Manual for more details)

Power

D-sub 50 pins

(Female)

Cable gland
IP67 (EN60529)

AIS - cable 21x2x0,14 6x1,0

halogenfree

Cable gland
IP67 (EN60529)

Header 50 pins

3 meter

Ter m i n al (A )

(12~24 VDC Input)

(RED)

(BLK)

GYRO

ROT

RANGE

LONG

RTCM

SC 104

unit

(Refer to MX535 AIS Transponder Technical & Installation Manual for more details)

Note: Port 5 (In/Out) is hard-wired to Ch4 (ECDIS) and Port 8 (Out) is hard-wired to Ch2 (Sensor 2).

External wiring for these ports is not necessary when

using the JB-50 with the MX420 and the MX535 AIS Transponder.

.

Figure 4.23 - MX420/AIS/MKD CDU & MX535 (NAUTICAST) Transponder System Wiring Diagram with JB-50 Junction Box

MX 420 Installation and Service Manual

SECTION 5

INSTALLATION NOTES

50

MX 420 Installation and Service Manual

51

MX 420 Installation and Service Manual

GENERAL

All configurations of the MX420 Control and Display Unit (CDU) are splashproof and
can be installed both above and below deck. To ensure that the back of the display unit
remains splashproof, protection covers must be used around the connectors. The
installation should meet the requirements of the helmsman, the crew or other users.
When flush mounted, locate a smooth and flat surface to insure that the gasket makes
full contact with the mounting surface. Ensure that the navigator is mounted in a place
where water flows off easily. Avoid places where water may accumulate for any

period of time.

Electronic Connections

Refer to figures in Section 3 for the drawing of the display console and Section 4 for
interface cables. The MX420/2 has one interface connector at the back, while the
MX420/8 and MX420/AIS models have three. The power and data I/O cable (Cable A)
and antenna cable are standard in the MX420/2 and MX420/8/AIS models. Cables B
and C are only supplied with the MX420/8 and MX420/AIS. All 18-wire I/O cables are
2 meters long and are clearly tagged with the letter designation near the connector
end. Cable A is pre-wired with a female 18-pin connector while cables B and C are
pre-wired with male 18-pin connectors. These data cables are not interchangeable.
When ordering these cables, please specify the part number and description as

described in the list of components in Section 1 of this manual.

Wire Preparation Procedure

Cables A, B & C are all 9-pair shielded cables. We recommend that the main cable
insulation (black plastic) be stripped about 5 inches back to expose the 9 color-coded
leads. Stripping each of these leads will expose the two wires in each pair, as
follows:

RED ---------- Red & Red/White
BROWN ----- Brown & Brown/White
PURPLE ---- Purple & Purple/White
ORANGE --- Orange & Orange/White
YELLOW --- Yellow & Yellow/Black
GREEN ------ Green & Green/White
BLUE -------- Blue & Blue/White
BLACK ------ Black & Black/White
GRAY -------- Gray & Gray/Black

Strip the individual wire insulation about 1/2 inch to make it more convenient to connect
the wires to the terminal strip posts and cut the shield wires short if not used. Use
electrical tape or shrink tubing to protect exposed shield wires. Use a 20-position
terminal strips to terminate each cable. This item is not supplied with the product, we
suggest getting it from a local electronic store. For more wiring details, please refer to

pages 33, 34 and 35 of this installation manual.

External Power

The MX420 was designed to operate on 12 ~ 32 VDC supply. It can tolerate voltages
no lower than 10 volts and no higher than 35 volts. It draws about 1 Ampere at 12 VDC
(with a MX421/B antenna connected). Power input connection is done through Cable

52

MX 420 Installation and Service Manual

A. Power wire colors are red (+) and black (-). Refer to Figure 4.1 for wiring hookup.
Even though the navigator has a reverse polarity protection device, we recommend
that the installer observe proper polarity before hooking up the power leads. MX
Marine also recommends using a 2 amp. fuse in line with the red wire as close to the

battery as possible. This not only protects the navigator but also the cabling.

Navigator Grounding.

The electronics of the navigator are isolated from the external power supply. Connect
the navigator unit to ground to avoid static charge build up. This can be done in either
one of two ways:

1. Connect the Cable A shield to the boat’s Seawater ground.

2. Connect the grounding stud of the navigator to the boat’s Seawater ground.

Note : ‘Seawater ground’ is any electrically conductive material that is

directly in contact with sea water.

MX421 GPS ANTENNA INSTALLATION

Antenna Location

The GPS smart antenna (MX421) should be mounted with a relative clear view of the
horizon. Do not, mount the antenna on top of a very tall sailboat mast, as this may
degrade the COG and SOG calculations, particularly when in DGPS mode. Ensure
the antenna is placed outside the beam path of transmitting radar (typically +15
°horizontally from the array’s center point) and INMARSAT satcom (A, B, C, or M;
typically +10° from the array’s center point in any of the possible transmitting
directions and at least 5 meters from any side lobe or back lobe direction). The GPS
antenna should be mounted below and at least 5 meters away from these types of

antennas. Do not place it within 3 meters of a SSB or VHF radios or their antennas.

Antenna Options

Two antenna options are available for the MX420, namely:

• GPS only smart antenna (MX421 or MX421-10)

• Combined GPS and differential beacon smart antenna (MX421B or MX421B-10)

These antenna models look identical and they are wired the same way (refer to the
chart shown below). The antenna model is indicated on the serial number tag on the
underside of the antenna. The drive voltage to the antenna is 12 VDC +10%, and
normally provided by the MX420. However, power to the MX421 antenna may be taken

from the main battery supply.

Antenna Connector

The multi-pin connector at the bottom of the antenna housing provides the necessary
interfacing between the MX421 smart antenna and the MX420 CDU. Older production
MX421 antennas use 8-pin connectors while new build units (MX421-10) use 10-pin
connectors. The interface connections from pins 1 through 6 are common for all
MX421 configurations. Pins 7 & 8 are used for monitoring the beacon receiver status
(for the built-in beacon receiver) or for external RTCM correction. The additional two
pins on the newer production MX421 are used to output the 1 PPS signal as shown in

53

MX 420 Installation and Service Manual

N

N

the chart below. Refer to figures 4.14, 4.15 and 4.16 for the MX421 antenna wiring
diagrams.

MX421 Smart Antenna Configurations

Pin#Wire

Color

BLK/

1

SHIELD

2RED

3BLU

4BRN

5ORG

6GRN

7YEL

8WHT

9PRPL

PRPL/

10

GRY

8-Pin Conn. 10-Pin Conn. (MX421-10)

MX421

GPS

/C

/C

N/A N/A 1 PPS (+)

N/A N/A 1 PPS (-)

MX421B

DGPS

Negative Ground

+10.5 ~ 32 VDC

MX Marine Proprietary Message (LPM) In (-)

MX Marine Proprietary Message (LPM) In (+)

GPS Out (-)

GPS Out (+)

Beacon Status

Out (-)

Beacon Status

Out (+)

MX421-10

GPS

RTCM In (-)

RTCM I n (+ )

MX421-10B

DGPS

Beacon Status

Out (-)

Beacon Status

Out (+)

Antenna Cable Options

The antenna cable is not provided with the MX421 antenna. The installer has to
determine the length needed and specify the length when ordering the cable. The
following cable lengths are available:

• 15 meter, twisted pair, 10-lead cable -- P/N 725637

• 20 meter, twisted pair, 10-lead cable -- P/N 3508 102 70170

• 40 meter, twisted pair, 10-lead cable -- P/N 3508 102 70180

• 90 meter, twisted pair, 10-lead cable -- P/N 3508 102 70190

External Differential Connection

Differential corrections from an external beacon receiver can only be connected to
the MX421-10 GPS model. Connections are done directly through Pins 7 (yellow)
and 8 (white) of the MX421-10 antenna cable. It will accept the RTCM SC-104

signal at 4800 baud.

MX420 NAVIGATOR INSTALLATION

The Navigator or CDU is the primary unit with the integrated display and keypad.
The navigator can be mounted using one of three techniques:

• Gimbal mount (supplied)

• Flush mount (supplied)

• Frame mount (optional)

54

MX 420 Installation and Service Manual

Each of these techniques are described below. All the hardware necessary to com­plete the Flush and Gimbal mount is provided with the MX420. You will need rear panel
access to complete these types of mounts. The Frame mount is an option for applica­tions where front panel removal is not desired or rear panel access is not available.
The hardware necessary for the Frame mount is sold separately (P/ N 715707). It is
important to consider the space behind the unit to prevent sharp cable bends before
commencing with the installation. A minimum of 100 mm. free space is needed behind

the unit for cable dressing.

Gimbal Mounting

A pivot Mounting Bracket including finger screws and rubber friction washers are
delivered with the MX420. Place the self-adhesive rubber washers around the two
threaded holes at each side of the navigator. Use the two machine screws with the
large palm grips to secure the MX420 to the mounting bracket. Adjust the viewing angle

to meet your needs.

Flush Mounting

Drilling and cutting instructions for flush mounting are given in Figure 3.3. The maximum
bulkhead thickness which can be used in this configuration is 9 mm (7/ 16 in). Cut a
notch deep enough to accommodate the flush mount bracket, Allen head bolt, and Allen

key for thicker bulkheads

Flush Mount Frame

If access to tighten the screws from the backside is impossible, an optional Flush
Mounting Frame is available (P/ N 715707). First, mount the frame to the navigator.
Next, attach all of the hardware interfaces to the appropriate port (i. e. Cable A, B & C).
Finally, mount the entire assembly to the panel from the display side. The frame is
oversized ( 300 mm x 175 mm; 11.81 in x 6.89 in). The frame mount hole cut dimensions

are given in Figure 3.5.

Turning Power On and Off

The navigator is turned on by briefly pressing the key. Please do not keep the key

pressed for more than one second, as this will turn the navigator off again when the
key is released. This key is also used to turn the power off by either of two methods:

a) Software Control:

A normal short key press displays the softkey option boxes Yes or No to turn the
power off. Respond by pressing the Yes softkey under the box turns the navigator
off. Selecting No cancels the operation, and returns the unit to normal operation.

b) Hardware Control:

Pressing the power key for more than 3 seconds, turns the power off under
hardware control (the softkey option will also be displayed under normal operating
conditions). The MX420 can not be turned on again for 10 seconds when this
method is used. Attempting to turn the unit on during this 10 second period, will only
activate the navigator for as long as the key is not released. This option is not
normally used, and is provided as an emergency alternative to the software power

control.

55

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 interface. 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 interfaces. 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 open
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.

56

MX 420 Installation and Service Manual

Speed Over Ground Pulse Output

The MX420 outputs the GPS calculated speed over ground in a pulse format. Refer to
the Specifications section of this manual for signal characteristics.

The pulse output is derived from either NMEA 1 or 2 ports (shared with the NMEA 0183
protocol) on the MX420. Therefore, these ports are available for either pulse output or
NMEA 0183 output. Don’t forget that only NMEA2 Out (Port2) can be either RS-232 or
RS-422 port. Pulse output NMEA1 is connected to the cable ( A) connector pins 6
(signal) and 7 (return; not ground). Pulse output Port 2 is connected to the cable (A)
connector pins 14 (signal) and 15 (return; not ground). These are RS-422 level
signals, and may not be compatible with every installation.

To setup the MX420 software, select the CFG1/Log Pulses screen. This screen
controls the output port (Pulse) of the speed over ground log output from the MX420 at
a user determined pulse rate of 100 to 500 pulses per nautical mile (200 is the pre-

selected value). The default condition of the Speed-Over-Ground output is not active.

External Alarm Output

The MX420 is held open (floating) during normal operations. In an alarm condition, the
external alarm pin is switched to ground potential. When an alarm condition is cleared
or acknowledged, the Ext. alarm signal will return to open condition automatically
(refer to table below for relay conditions). However, it is possible to retain the external
alarm condition by setting the “Retain external alarm:” to ON. At this setting, the

external alarm signal can only be cleared by correcting the problem.

Ext. Alarm Relay Conditions

MX420 turned OFF Energized

MX420 Turned ON
(No Alarm)

MX420 Turned On
(With Alarm)

12 VDC Input Powe r
Failure

Not Energized

Energized

Energized

57

MX 420 Installation and Service Manual

The external alarm is derived from the “ALARMout” port on cable (A) pin 18 (Black/
White - ALARMout). The software is setup in each of the appropriate CFG1 (Alarms)
menu. The relay coil supply voltage must be connected to an independent battery
backed-up alarm supply. Make sure the relay coil voltage is compatible with the
voltage rating of the alarm power supply (i.e. NTE Electronics Relay - P/N R14-11D10­12 for use in a 12 VDC supply). The negative ground of the alarm power supply must
be connected to the “GND. to MX421” shield wire in Cable A (refer to the relay diagram

below).

To a Battery Back-Up
Alarm Power Supply

+

-

MX 420

Cable A
Pin 1 (Shield)
(Gnd. To Mx421)

Cable A
Pin 18
ALARMout

Coil

N.C.

Continuous-Duty
SPDT Relay
(12 VDC < 75 mA)

C

N.O.

Port 2: RS- 422 / RS- 232 Serial Interface

The CDU has a standard RS- 232 interface (similar to a PC COM). The RS-232 use the
same internal UART logic as the NMEA port 2. The TxD RS- 232 output and the NMEA2
out RS- 422 output carries the same serial data, but with the electrical levels of each
standard. The input is shared, and can only be set up to either receive RS- 232 input

or NMEA RS- 422 input.

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MX 420 Installation and Service Manual

A

1

15

2
3

3

1Z

1A

2

1Y

13

4Z

4A

14

4Y

5

2Z

2A

6

2Y

11

3Z

3A

10

3Y

G

G

A

7

DY

DA

5

RY

RS

6

RTC

RS-422

NMEA2 Out A

NMEA2 Out B

RS-232

TXD

Conn.A

14

15

17

Figure 5.1 Port 2: RS- 422 / RS- 232 Port Schematic

MX420 PC Interface

The diagram below shows the bi-directional (RS-232) interface between the MX420
(NMEA2 port in Cable A) and a PC serial port.

PC CONN.

DB9S

(Female)

Ter mi nal Str ip

GRN/WHT

SHIELD (BLK)

GREEN

GRAY

RED

BLACK

Mx420

CABLE (A)

13 - NMEA2 IN (B)

1 - GND

12 - NMEA2 IN (A)

17 - NMEA2 TXD

(RS-232)

2 - PWR IN (+)

3 - PWR RET (-)

+12 VD C

NEG.

NMEA Interface

The MX420 meets the NMEA 0183 version 2.1 electrical standard for marine interface
communications with other marine equipment, such as:

Radars, Plotters, Autopilots, Fish Finders, etc.

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MX 420 Installation and Service Manual

There are differences in the electrical interface specification between NMEA 0183
version 1.5 (introduced in 1987) and NMEA 0183 version 2.0 and later (introduced in

1994). Some older model equipment utilize RS-232, others use RS-422, and others
meet the older version 1.5 specification. In an effort to simplify your interface capabili­ties, you should take the time to determine which electrical interface specification all of

the interfaced equipment meets.

NMEA Interface to other Equipment

The MX420 meets NMEA 0183 version 2.1 electrically, and in protocol. As version 2.1
is not necessarily compatible with the older version 1.5, the differences in hardware
are mentioned here to avoid possible conflicts:

Listener:

The listener input works with a threshold of 2 volts compared to the former 4 volt. It is
still an insulated input and, in general, there should not be any interface problems
receiving data from the older
standard.

Talker:
The talker output is a RS-422 output:
NMEA talker output B is active compared to GND or shield of the navigator. In the old

version, output B was normally tied to GND or shield.

The maximum drive voltage between the talker A and B outputs is ±6 volt.

Compared to the former 0 to 15 volt output, the negative voltage between the talker
A and B output may be a problem on older listeners which do not meet the new

standard.

The minimum output voltage may be as low as ±2 volt. This is not compatible with
the former 4 volt input threshold and may be the cause of interface problems. If this

is the case, try using the MX420’s RS-232 interface. This may more likely solve the
problem. Otherwise third party conversion boxes may be necessary.

Cables provided for the NMEA signals are shielded pairs. If extension cables are
needed, be sure to use similar shielded pair cables in order to avoid spurious signal
radiation. More than one NMEA listener can be connected in parallel to the same NMEA
talker. The maximum number of listeners connected to a single talker is dependent on
the combined listener input impedance’s, and the capacity available for data through-

put.

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MX 420 Installation and Service Manual

MX420 NMEA 0183 Sentences

The NMEA Standard provides for asynchronous transmission, with a single Talker and
multiple Listeners per line. Typical use includes information transfer from electronic
positioning and navigational devices to autopilots, plotters, terminals, printers, etc.

The NMEA 0183 Standard uses an 8 bit ASCII block oriented protocol, that is not
compatible with the NMEA 0180 simple format or the NMEA 0182 complex format due to

differences in data format, baud rate and parity bits.

Data Format

Data are transmitted in different sentences, each containing one or more data fields. A
field consists of a string of characters immediately preceded by a “,” (comma) charac­ter, except for the first (address) field which is preceded by “$”, indicating the begin­ning of a new record. Hex 0D 0A <CR>< LF> - end of sentence - must follow the last
field in each sentence.

The data fields are identified only by their position within the sentence as deter­mined by the field delimiters (comma). Numerical data fields within a sentence may
vary in length from one sentence to another, depending on the precision available.

Data field position is therefore determined only by counting “,” (commas) rather than
counting the total number of characters from the beginning of the sentence.

The last data field is not followed by a comma delimiter. When a checksum is used,
the last data field is followed by an asterisk “*”, indicating that the checksum
follows. The checksum is the absolute value calculated by
exclusive -OR’ing the 8 data bits (no start bits or stop bits) of each character in the
sentence between, but excluding “$” and “*”. The hexadecimal value of the most
significant and least significant 4 bits of the result are converted to two ASCII
characters (0- 9, A- F) for transmission. The most significant character is transmit-

ted first.

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MX 420 Installation and Service Manual

9

r

Example:

Field #: 1 2 3 4 5 6 7 8

$GPXTE,A,A,3.42,L,N*hh<CR><LF>

Units of measure, N=nautical miles

Direction to steer, L=Left, R=Right

Magnitude of error (nautical miles)

Not used, Always = A

Status: A=Data valid, V=Data invalid

Address: GP = Talker identifier: GPS
XTE= Sentence formatter: Cross-Track Error

Start of Sentence delimite

Sentence terminator

Optional checksum (HEX)
In Ver. 1.5 & 2.0, required in Ver 2.1

Checksum delimiter

NMEA Output Sentences

All sentences have the identifier “GP” for Global Positioning Systems. All position data
are in the user selected (displayed) datum except for GGA where the datum can be
manually set to WGS84, independent of the selected (displayed) datum.

RMB is transmitted only if an active route is present. Please refer to the Route section
of the Operator’s Manual for details on setting up an active route.

APA , APB , and XTE , are transmitted only if an active route is present and the
Autopilot Alarm in each of these NMEA sentence setup screens is Enabled and this

feature is not in an alarm condition.

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MX 420 Installation and Service Manual

ID DESCRIPTION ID D ESCRIPTION

* APA

Autopilot Sentence A

APB

Autopilot Sentence B

BOD

Bearing Origin to Destination

BWC

Bearing & Distance to Waypoint - Great
Circle

BWR

Bearing & Distance to Waypoint - Rhumb
Line

DTM

Datum Reference

GGA

GPS Fix Data

GLL

Geographic Position - Latitude/
Longitude

GRS

GPS Range Residuals

GSA

GPS DOP & Active Satellites

GST

GPS Pseudorange Noise Statistics

GSV

GPS Satellites In View

HDT

Heading, True

HSC

Heading Steering Command

MSK

MSK Receiver Interface

MSS

MSK Receiver Signal Status

*

APA , Rnn

designs.

and

SNU

are older sentence formats (version 1.5) not recommended for new

Recommended Minimum

RMB

Navigation Information
Recommended Minimum

RMC

Specific GPS/ Tra nsi t Da ta

*Rnn

Routes

ROT

Rate of Turn

RTE

Routes

*SNU

Loran- C SNR Status

VDR

Set & Drift

VHW

Water Speed and Heading

VPW

Speed Measured Parallel to Wind

Course & Speed Over

VTG

Ground

WCV

Waypoint Closure Velocity

WPL

Waypoint Location

XTE

Cross- Track Error, Measured

ZDA

Time & Date

UTC & Time to Destination

ZTG

Waypoint

Table 5.1 NMEA 0183 Output Sentences

Input NMEA 0183 Sentences

The MX420 recognizes version 1.5, 2.0,2.1 and 2.3 NMEA input records. The MX420
can utilize the following input sentence formats:

Depth: DBK, DBS, DBT, and/ or DPT

Gyro: HCC, HDM, HDT, RMA (only when GPS is not available), RMC (only when GPS is

not available), VHW, and VTG (only when GPS is not available)

Position: GLL, RMA, RMC (only when GPS is not available)

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MX 420 Installation and Service Manual

Speed: RMA , RMC , VHW, VTG (only when GPS is not available) or pulses-per-
second

Transducer: MMB, XDR

Waypoints: The received WPL data will overwrite the memory content of the waypoint

location which is contained in the received WPL sentence

The MX420 does not process the TALKER identifier (first two characters following the
$ of NMEA 0183 sentences) for any NMEA sentences received. Any pair of characters

within the NMEA specification are recognized.

The MX420 does process floating numerical formats in the received sentences.

Although the current version of the NMEA 0183 standard requires that a checksum be
present, the checksum is not required by the MX420. However, if the checksum is
included in the NMEA sentence, the MX420 will reject any sentence where the checksum

and data do not correlate.

Viewing Input Data

You can view data being sent to the MX420 by other equipment or loop a MX420
output port back to an unused input port to verify if it is outputting data to other
equipment. This is a great tool to use when you are first interfacing equipment.

To activate the Input Data screen:

Press CFG.

Scroll through the menu and select Operation.

Press E and change Engineering Display from No to Yes.

Press E again to exit the edit mode.

Press the left cursor key until the CFG3 Input Data screen is displayed.

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MX 420 Installation and Service Manual

Press the up or down cursor key until the proper input port number is
selected.

The data that you will see on the screen is unprocessed. Therefore, if there are
errors in the data, you can compare the data against the NMEA 0183 standard.
You can also use this screen to verify that data is being received from external

RTCM sources or other equipment communicating with the MX420.

Dual Control (Remote) Interface

The Dual Control mode, which is enabled in the CFG Dual Contr. screen, allows
you to connect two MX420s in a Master / Slave configuration where a common
database is shared between two MX420 control heads. This configuration also
allows you to use one antenna connected to the Master unit, for both MX420s. The
remaining data ports, the MOB /Event input port, and the alarm output ports are still
available on each unit for individual use on each MX420.

The hardware interface is accomplished by connecting NMEA Output 1 to NMEA
Input 1 between the two units.

MX420/8 or MX420/2

MASTER UNIT

CABLE A

PORT 1

BRN [NMEA1 IN (A)]

BRN/WHT [NMEA1 IN (b)]

PRPL [NMEA1 OUT (A)]

PRPL/WHT [NMEA1 OUT (B)]

SHIELD

4

5

6

7

1

MX420 Dual-Control Data Interface

65

MX420/8 or MX420/2
SLAVE UNIT

CABLE A
PORT 1

SHIELD

1

6

PRPL [NMEA1 OUT (A)]

7

PRPL/WHT [NMEA1 OUT ( B)]

4

BRN [NMEA1 I N (A)]

5

BRN/WHT [NMEA1 IN (B)]

No Antenna
Connected

MX 420 Installation and Service Manual

The interface between the two units takes place over a high speed data link. The
master unit must be connected to the smart GPS antenna unit (MX421). The master unit
receives the position data then transfer it to the slave unit at a one second rate (the
same as the position calculation). Due to the high speed data link, there is virtually no
visible position delay between the two units.

When the two units are first configured as master and slave, the master listens for a
configuration polling message from the slave. Once the master recognizes the slave’s
polling message, the Common Data Base (see Table below) is downloaded from the

master to the slave. This function also takes place each time the units are powered up.

Table 5. Master / Slave Common Data Base

The items detailed in Table 6 are independently controlled at the individual MX420
control heads.

Table 6. Independently Controlled Functions

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MX 420 Installation and Service Manual

MX420 Dual Control with Integrity Monitor

The Integrity Monitor (IM) feature (once the license is enabled) allows the two dual-control
MX420/8 units to constantly compare each of the two GPS solutions and, if configured to do
so, give an alarm and/or switch to the use of the “best” GPS solution.

Both Master and Slave units are functional GPS receivers and both continuously calculate GPS
solutions. The IM continuously compares the two position solutions. If the GPS Source is set
to Automatic, it begins by using the Master calculated position. However, it continuously
compares the “used” solution to the “other” solution. If the “other” solution is better, it will
switch to use that position solution. Essentially, the Master mode will transfer automatically to

the unit whose position solution is being used for navigation.

MX 420/8

MASTER UNIT

CABLE A

BRN [NMEA1 IN (A)]

BRN/WHT [NMEA1 IN (b)]

PRPL [NMEA1 OUT (A)]

PRPL/WHT [NMEA1 OUT (B)]

SHIELD

PORT 1

4

5

6

7

1

MX 420/8
SLAVE UNIT

CABLE A
PORT 1

SHIELD

1

6

PRPL [NMEA1 OUT (A)]

7

PRPL/WHT [NMEA1 OUT (B)]

4

BRN [NMEA1 IN (A)]

5

BRN/WHT [NMEA1 IN (B)]

MX 421B Antenna
Connected

MX420 Dual Control with Integrity Monitor Data Interface

Once the Dual Control IM is enabled, CFG1/Dual Control screen looks
like this:

DUAL CONTROL
Mode: Master (options: Master, Slave)
Dual Control: Yes (options: Yes, No)
GPS Source: Automatic (options: Automatic, Master, Slave)
Integrity Alarm: Ye s (options: Yes, No)
GPS Source: Master (options: Master, Slave)
Dual Status: OK (options: OK, No Comm, Mirroring)

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MX 420 Installation and Service Manual

To enable the functionality of the Dual Control Integrity Monitor, you
must set the following to:

Dual Control: Yes
GPS Source: Automatic

If you want the alarm to sound when the GPS source is switched:

Set the Integrity Alarm to Yes

MX420/AIS Installation

There are two variation of the MX420/AIS models, namely:

• MX420/AIS Basic System (MKD)

• MX420/AIS DGPS Navigation System

The MX420/AIS Basic or MKD system is primarily a control and display unit (CDU)
for the MX423 AIS transponder. GPS Position data is supplied by the GPS engine
in the transponder. The MX420/AIS Basic does not perform navigation calcula­tions. Displays functions like the NAV, TIDE and GPS are inactive. In addition,
some display pages like POS3, AUX3, and AUX5 are also inactive when no
MX421 (smart GPS antenna) is connected to the CDU. A third party external GPS
source may be used to provide position data to the transponder.

The MX420/AIS Navigation system performs both the CDU functions to the AIS
transponder and navigation functions just like any regular GPS navigator. The
MX420/AIS Basic and the MX420/AIS Navigation Systems are essentially identi­cal control and display unit. The main difference is the addition of the MX421
smart antenna and the activation of the AIS option (AIS license is required). The
MX420/AIS detects the presence of the MX421 antenna and makes the full
navigation function available to the user. Refer to pages 39 and 41 for AIS wiring

diagram.

Other MX420/AIS Interface

In addition to Speed and Gyro (ROT) interface, it is suggested to connect the
MX420/AIS CDU to the following equipment:

• MX423 AIS Transponder - NMEA 5 (required)

• Long-Range Communication (INMARSAT-C) - NMEA 6 (optional)

• ECDIS Chart - NMEA 7 (optional)

These equipment requires high-speed connection to the MX420. NMEA 5 through
10 are high-speed ports capable of handling baud rate speeds up to 115.2 Kbps.
We recommend interfacing these equipment to the NMEA ports listed above for

better results.

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MX 420 Installation and Service Manual

ECDIS/
ARPA

MX 422 Professional DG PS Navigato r

GPS

Beacon

Optional MX421/B

GYRO

Long­Range

Pilot­Port

GPS

Config

Log

VHF

MX420 AIS Basic configuration

MX423 AIS Transponder Interface

The NMEA 5 port of the MX420/AIS (or MKD) connects to the bidirectional PSP port of
the MX423 AIS transponder (see the schematic diagram on figure 4.18 on page 41).
Communication speed between the MX420 and the transponder is preset at 57.6
Kbps.

Refer to the MX423 AIS Shipborne Class A Transponder installation manual for more
details.

Troubleshooting Guide

The MX420 is virtually maintenance free. There are, however, a few important points
to note.

Please check your installation carefully before returning the MX420 to the dealer or
factory for service. A few troubleshooting tips follow.

The MX420 performs a variety of self tests during normal operation. If a function fails
the self test, the navigator displays an Internal Error message every one minute.

69

MX 420 Installation and Service Manual

Problem Diagnosis

No response: (Black LCD display and no
traffic light)

No keyboard response or partial keyboard
response

Battery low alarm

No position update; won’t track satellites
(Red traffic light blinking for more than 10
minutes)

No position update; tracking satellites
(Red traffic light solid all the time)

All data lost at power up

No DGPS update; not tracking beacon
station

No data output to peripheral equipment

No external power supply
Check supply voltage
Check for reverse polarity
Check wire installation

Check if external fuse is blown

Corrupted memory
faulty keyboard
faulty processor

Return the unit for repair

External battery low
Check power supply voltage and
installation

Jamming by other on- board or adjacent
transmitters
Faulty antenna or antenna cable
Relocate GPS antenna
Connect the MX421 power directly to the
external 12 VDC supply.
Replace antenna
Return the unit for repair

DGPS mode set to DGPS Only and no
corrections are being received
GPS satellite signals weak (satellites
dropping in and out)
Check maximum cable length restrictions
and cable condition (for weak satellite
signal condition)
Return the unit for repair

Backup battery is dead
Replace the internal backup battery

DGPS mode set to Off, so no corrections
are being received.
Station Select is set to Manual.
Faulty antenna

NMEA output data not configured
Wrong NMEA version
Wrong output rate, or format
Wrong electrical standard
Too many data sentences turned on
(throughput overflow)
More than one NMEA talker on the circuit
Faulty port
The MX420 requires the user to enable
NMEA

Return the unit for repair

70

MX 420 Installation and Service Manual

Memory Backup Battery

The internal real time clock and memory which stores the waypoints, alarm limits, etc.,
is backed up by a lithium cell battery. The expected life time is 2 years at 21° C, but this
is based on the temperature the navigator is stored at when not in use. The higher the

temperature, the shorter the life and vice versa.

Backup Battery Replacement

Marine electronics dealers or radio supply stores will typically stock the replacement
battery, Type CR2032, 3V Lithium battery.

The battery is mounted in a socket located on the MX420 processor board. MX Marine
recommends this service to be done by a qualified service technician.

MX420 PC Interface

The diagram below shows the RS-232 interface between the MX420 (NMEA2 port
only) and a PC serial port.

PC CONN.

DB9S

(Female)

+12 VDC

Ter mi nal St ri p

GRN/WHT

SHIELD (BLK)

GREEN

GRAY

RED

BLACK

NEG.

Mx420

CABLE (A)

13 - NMEA2 IN (B)

1 - GND

12 - NMEA2 IN (A)

17 - NMEA2 TXD

(RS-232)

2 - PWR IN (+ )

3 - PWR RET (-)

PC Interface Cable Diagram

Software Download Procedure

Tools, cables and software needed:

· Power/Download cable (or refer PC Interface Cable Diagram above)

· DC power supply 12-24 VDC

· PC with DOS or DOS prompt under Windows xx

· Download program dlmx400.exe and Dos4gw.exe

· *.hex file – the program itself

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MX 420 Installation and Service Manual

Procedure:

1. Install the download program dlmx400.exe, dos4gw and the *.hex file in the same

2. Using a pre-made Power/Download cable, connect the power cable to the power

3. Connect the DB9 connector to COMM1 (RS232) serial port of the PC.

4. Connect the 18-pin connector (or Cable A) to the MX420/MK12.

5. Turn the MX420/MK12 on to verify if power connection is correct. Turn it off

6. The download program runs much faster under DOS than under Windows.

7. At the command prompt type dlmx400 *.hex. (where *.hex is the program file

8. The program will ask you to turn the navigator on. When this has been done

9. The traffic lights will turn from red to yellow and then to green.

10. When the download is finished the computer will return to the DOS prompt.

Hint:

It is highly recommended that the MX420 navigator be cold started after
downloading the program. Please note that all settings including waypoints and
routes will be lost.

This is important to flush out the residual memory, which may cause problems
with the operation of the unit.

Memory Clear Procedure:

1. After downloading the software, turn the power off to the MX420 by turning

2. Press and hold down the right-most softkey.

3. Apply 12-volt power to the unit and wait for about 5 seconds. The MX420

directory (i.e. MX Marine).

supply. Black wire to ground and blue wire to +12-24V.

again.

However, if a DOS-PC is not available, you can also use the DOS prompt
under Windows 95, 98, NT, etc.

name)

the file will be loaded into the download program and after a short while a
short line starts to turn in the right hand side of the computer screen.

Turn the main power supply switch OFF and ON and verify the program
version in the AUX 7 display. Under the AUX7 screen, press the left-most

softkey 3 times to show the complete program build number (i.e. V1.5(751).

off the 12 VDC circuit breaker (this may also be accomplished by removing
the “Cable A” from the back of the unit).

will come on and display the MX Marine logo.

4. Release the softkey.

5. The memory is now cleared.

72

MX Marine

A division of NAVICO, Inc.

23868 Hawthorne Blvd., Suite 201

Torrance, CA 90505

USA

[phone] Telephone

[phone] Fax

Internet: www.mx-marine.com