Garmin GHP Compact Reactor Hydraulic Installaiton Instructions page 10

• The internal NMEA 0183 ports and communication protocols
are configured on the connected Garmin device. See the
NMEA 0183 section of the chartplotter owner's manual for
more information.
• The ground wires on the NMEA 0183 data cable and your
NMEA 0183 device must both be connected to ground.
• When connecting NMEA 0183 devices with two transmitting
and two receiving wires, it is not necessary for the NMEA
0183 devices to connect to a common ground.
• When connecting a NMEA 0183 device with only one
transmitting (Tx) wire or with only one receiving (Rx) wire, the
NMEA 0183 devices must be connected to a common
ground.
• For two-way communication with a NMEA 0183 device, the
internal ports on the NMEA 0183 data cable are not linked.
For example, if the input of the NMEA 0183 device is
connected to the internal output port 1 on the data cable, you
can connect the output port of your NMEA 0183 device to
any of the internal input ports (port 1, port 2, port 3, or port 4)
on the wiring harness.
• There are four internal NMEA 0183 input ports (Rx ports),
and two internal NMEA 0183 output (Tx ports) on the
included NMEA 0183 data cable. You can connect one
NMEA 0183 device per internal Rx port to input data to your
Garmin device, and you can connect up to three NMEA 0183
devices in parallel to each internal Tx port to receive data
output by your Garmin device.
Two-Way NMEA 0183 Communication
NMEA 2000 network (provides power to the helm control)
12 Vdc power source
Helm control
NMEA 0183-compatible device
Wire Helm Control Wire Color —
Function
N/A
N/A
Blue — Tx/A (+)
White — Tx/B (-)
Brown — Rx/A (+)
Green — Rx/B (-)
NOTE: When connecting a NMEA 0183 device with two
transmitting and two receiving lines, it is not necessary for the
NMEA 2000 bus and the NMEA 0183 device to connect to a
common ground.
Only One Receiving Wire
If your NMEA 0183-compatible device has only one receiving
wire (Rx), it must be connected to the blue wire (Tx/A) from the
helm control, and the white wire (Tx/B) from the helm control
must remain unconnected.
10
NMEA 0183-Compatible
Device Wire Function
Power
NMEA 0183 ground
Rx/A (+)
Rx/B (-)
Tx/A (+)
Tx/B (-)
NMEA 2000network (provides power to the helm control)
12 Vdc power source
Helm control
NMEA 0183-compatible device
Wire Helm Control Wire Color —
Function
N/A
N/A
Blue — Tx/A (+)
White — unconnected
Brown — Rx/A (+)
Green — Rx/B (-)
NOTE: When connecting a NMEA 0183 device with only one
receiving (Rx) line, the NMEA 2000 bus and the NMEA 0183
device must be connected to a common ground.
Only One Transmitting Wire
If your NMEA 0183-compatible device has only one transmitting
wire (Tx), it must be connected to the brown wire (Rx/A) from the
helm control, and the green wire (Rx/B) from the helm control
must be connected to NMEA 0183 ground.
NMEA 2000 network (provides power to the helm control)
12 Vdc power source
Helm control
NMEA 0183-compatible device
Wire Helm Control Wire Color —
Function
N/A
Green — Rx/B (-) (connect to
NMEA 0183 ground)
Blue — Tx/A (+)
White — Tx/B (-)
Brown — Rx/A (+)
NOTE: When connecting a NMEA 0183 device with only one
transmitting (Tx) line, the NMEA 2000 bus and the NMEA 0183
device must be connected to a common ground.
NMEA 0183-Compatible
Device Wire Function
Power
NMEA 0183 ground
Rx
N/A
Tx/A (+)
Tx/B (-)
NMEA 0183-Compatible
Device Wire Function
Power
NMEA 0183 ground
Rx/A (+)
Rx/B (-)
Tx/A (+)