Garmin GNX 20 Marine Instrument Installation Instructions

GNX™ 20/21 Installation Instructions

To obtain the best possible performance, install this marine

instrument according to these instructions. If you experience

difficulty during the installation, contact Garmin

®

Product

Support, or seek the advice of a professional installer.

This instrument communicates with NMEA 2000

®

sensors and

devices, and shows information such as speed, heading, and

water depth when connected to the appropriate sensors. The

instrument can also communicate with a NMEA

®

0183 device

using an optional data cable.

Important Safety Information

WARNING

See the

Important Safety and Product Information

guide in the

product box for product warnings and other important

information.

CAUTION

Always wear safety goggles, ear protection, and a dust mask

when drilling, cutting, or sanding.

NOTICE

When drilling or cutting, always check what is on the opposite

side of the surface.

Registering Your Device

Help us better support you by completing our online registration

today.

•

Go to

http://my.garmin.com

.

•

Keep the original sales receipt, or a photocopy, in a safe

place.

Contacting Garmin Product Support

•

Go to

www.garmin.com/support

and click

Contact Support

for in-country support information.

•

In the USA, call (913) 397.8200 or (800) 800.1020.

•

In the UK, call 0808 2380000.

•

In Europe, call +44 (0) 870.8501241.

Mounting Considerations

NOTICE

This device should be mounted in a location that is not exposed

to extreme temperatures or conditions. The temperature range

for this device is listed in the product specifications. Extended

exposure to temperatures exceeding the specified temperature

range, in storage or operating conditions, may cause device

failure. Extreme-temperature-induced damage and related

consequences are not covered by the warranty.

The mounting surface must be flat to avoid damaging the device

when it is mounted.

Using the included hardware and template, you can flush mount

the device in the dashboard. If you want to mount the device

using an alternative method where it appears flat with the front

of the dashboard, you must purchase a flat-mount kit

(professional installation recommended) from your Garmin

dealer.

When selecting a mounting location, observe these

considerations.

•

The mounting location should be at or below eye level to

provide optimal viewing as you operate your vessel.

•

The mounting location should be at less than a 45° viewing

angle for the GNX 20 Marine Instrument with Standard LCD

and less than a 50° viewing angle for the GNX 21 Marine

Instrument with Inverted LCD. Screen color inversion occurs

when the viewing angle is greater than 30° in the 9 o'clock

direction on the GNX 20 and when the viewing angle is

greater than 60° in the 1 o'clock direction on the GNX 21.

•

The mounting location should allow easy access to the keys

on the device.

•

The mounting surface must be strong enough to support the

weight of the device and protect it from excessive vibration or

shock.

•

To avoid interference with a magnetic compass, the device

should not be installed closer to a compass than the

compass-safe distance value listed in the product

specifications.

•

The area behind the mounting surface must allow room for

the routing and connection of the cables.

Mounting the Device

NOTICE

If you are mounting the device in fiberglass, when drilling the

four pilot holes, it is recommended to use a countersink bit to

drill a clearance counterbore through only the top gel-coat layer.

This will help to avoid any cracking in the gel-coat layer when

the screws are tightened.

Stainless-steel screws may bind when screwed into fiberglass

and overtightened. Garmin recommends applying an anti-seize

lubricant to the screws before installing them.

The included template and hardware can be used to flush

mount the device in your dashboard. To mount the device so

the screen is flat with the dashboard, you must purchase a flat-

mount kit from your Garmin dealer.

1

Trim the flush-mount template and ensure it will fit in the

location where you plan to mount the marine instrument.

The flush-mount template is included in the product box.

2

Remove the liner from the adhesive on the back of the

template and apply it to the location where you plan to mount

the marine instrument.

3

If you plan to cut the hole with a jigsaw instead of a 90 mm

(3.5 in.) hole saw, use a 10 mm (

3

/

8

in.) drill bit to drill a pilot

hole to begin cutting the mounting surface.

4

Using the jigsaw or the 90 mm (3.5 in.) hole saw, cut the

mounting surface along the inside of the dashed line

indicated on the flush-mount template.

5

If necessary, use a file and sandpaper to refine the size of

the hole.

6

Place the marine instrument into the cutout to confirm that

the mounting holes on the template are in the correct

locations.

7

If the mounting holes are not correct, mark the correct

locations of the mounting holes.

8

Remove the marine instrument from the cutout.

9

Drill the 2.8 mm (

7

/

64

in.) pilot holes.

If you are mounting the marine instrument in fiberglass, use

a countersink bit as advised in the notice.

10

Remove the remainder of the template.

11

Place the included gasket on the back of the device and

apply marine sealant around the gasket to prevent leakage

behind the dashboard.

January 2014

190-01659-02_0A

Printed in Taiwan

Section	Page
GNX 20/21 Installation Instructions	1
Important Safety Information	1
Registering Your Device	1
Contacting Garmin Product Support	1
Mounting Considerations	1
Mounting the Device	1
Connection Considerations	2
NMEA 2000 Connection Considerations	2
NMEA 0183 Connection Considerations	2
NMEA 0183 Connection Diagrams	3
Specifications	3
NMEA 2000 PGN Information	3

Garmin GNX 20 Marine Instrument Installation Instructions

Garmin GNX 20 Marine Instrument Manual

Garmin GNX 20 Marine Instrument manual content summary: