User manual

NMEA 0183 Buffer - NBF-3

Connecting to the NBF-3 Listener Port

Connecting an NMEA Talker

The input to the NBF-3 is labelled ‘Listener’ and this is where the NMEA Talker should be connected.

• Connect the NBF-3 Listener A/+ to the positive data line of the NMEA Talker.

• Connect the NBF-3 Listener B/- to the negative data line of the NMEA Talker.

This is the ground / common connection of the Talker for RS232 or NMEA 0183 version 1 Talkers.

• For details on the data indicator, refer to “NBF-3 Listener Port Data LED (Green)” on page 14.

Note: Only one NMEA Talker can be connected to the NBF-3 Listener port. Multiple NMEA Talkers require an NMEA

Multiplexer to be tted, see www.actisense.com/NDC-4.

Note: The NMEA Listener port is fully isolated and is compatible with all versions of NMEA 0183 and with RS422,

RS232 and RS485 voltage levels, see “Specications” on page 15.

Powering the Talker from the NBF-3 Listener Port

It is also possible to power the NMEA Talker from the NBF-3. The NBF-3 power connection is routed to the Listener port

PWR OUT connection via a self-resettable fuse. A maximum of 500mA can be provided to the NMEA Talker at the

voltage supplied to the NBF-3.

• Connect the NBF-3 +VE OUT to the positive supply input of the NMEA Talker.

• Connect the GND OUT of the NBF-3 to the negative supply or ground input of the NMEA Talker.

Note: The current provided is temperature dependant, see “Specications” on page 15.

Note: If the NBF-3 power supply is incorrectly wired (reverse polarity), the Listener power output voltage will also be

reverse polarity and could potentially harm any connected equipment. However the NBF-3 electronics are always

protected against reverse polarity supply faults.

Figure 4 - Listener Port Wiring Diagram

Latitude

50˚74’03”

Longitude

-1˚94’95”

Talker power: Positive

Talker power: Negative

Talker data: Negative

Talker data: Positive

Talker Device