Garmin GPSMAP 8X10 Installation Instructions Manual page 12

Lamp or Horn Connections
The device can be used with a lamp, a horn, or both, to sound or flash an alert when the chartplotter displays a
message. This is optional, and the alarm wire is not necessary for the device to function normally. When
connecting the device to a lamp or horn, observe these considerations.
• The alarm circuit switches to a low-voltage state when the alarm sounds.
• The maximum current is 100 mA, and a relay is needed to limit the current from the chartplotter to 100 mA.
• To toggle visual and audible alerts manually, you can install single-pole, single-throw switches.
Item Description
Power source
Power cable
Horn
Lamp
NMEA 0183 cable
Relay (100 mA coil current)
Toggle switches to enable and disable lamp or horn alerts
Item Wire Color
Red
Black
Yellow
12
Wire Function
Power
Ground
Alarm