FURUNO GP340 GNSS/SBAS Receiver, NMEA 2000/NMEA 0183 – GP340

Description

The FURUNO GP340 is a compact external GNSS/SBAS receiver designed to provide a fast, stable and highly accurate position source to marine electronics without adding another display to the helm. It is especially useful when an MFD, radar, instrument system, autopilot or data network needs a dedicated antenna/receiver with broad satellite coverage and a rapid position refresh. The GP340 automatically combines signals from multiple global navigation satellite systems and can feed that position data directly to an NMEA 2000 network using the supplied cable, or to compatible legacy equipment through an optional NMEA 0183 cable.

• Multi-constellation GNSS reception: Tracks GPS L1/L5, GLONASS L1, Galileo E1/E5, QZSS L1/L5 and BeiDou B1/B2 signals, giving the receiver a large pool of satellites from which to build a position solution.
• SBAS correction support: Supports WAAS, EGNOS, MSAS and GAGAN augmentation systems for improved positional accuracy wherever the relevant correction service is available.
• Up to 10 Hz position updates: Outputs position information as often as ten times per second, which produces smoother vessel movement on compatible chartplotters than slower one-second position sources.
• NMEA 2000 ready out of the box: Includes Furuno’s 6 m GP3-400-N2K-06 cable, terminating at a standard NMEA 2000 connector for straightforward integration with a properly powered backbone.
• Flexible installation: Surface/deck mounting and standard 1"-14 pipe/pole mounting are supported with the supplied mounting hardware, allowing the receiver to be positioned for a clear view of the sky.

Multi-Constellation Positioning

The GP340 is not limited to a single satellite system. It automatically uses an appropriate combination of available satellites from the supported GPS, GLONASS, Galileo, QZSS and BeiDou constellations. That matters on a boat because the visible sky can be partly obstructed by a hardtop, mast, tower, superstructure or nearby terrain. Access to more constellations increases the number of useful satellites available to the receiver and helps it maintain a dependable navigation solution as conditions change.

Furuno specifies an update rate of up to 10 Hz. For the operator, the practical benefit is a more fluid own-ship symbol, course-over-ground and speed-over-ground presentation on compatible displays, particularly during turns, close-quarters manoeuvring and faster running. Furuno’s technical information lists position performance of approximately 1 m CEP and less than 3 m at 95% under specified conditions, while SBAS services can further improve the solution where coverage is available.

NMEA 2000 Integration

The standard installation is NMEA 2000. The supplied 6 m cable has the GP340’s dedicated connector at the receiver end and a standard NMEA 2000 connection at the network end. Once connected to a correctly designed backbone, the GP340 can provide common navigation data including rapid position update, COG/SOG, GNSS position information, system time, dilution-of-precision information and satellites-in-view data to compatible equipment. Furuno rates the GP340 at one NMEA 2000 LEN, so its network load is very small.

The GP340 is compatible with a wide range of Furuno NavNet systems and can also serve other standards-compliant NMEA 2000 equipment. It is a useful choice when replacing an aging GPS antenna/receiver or when a networked helm would benefit from a dedicated external position source rather than relying solely on an MFD’s internal GNSS antenna.

NMEA 0183 for Legacy Equipment

For installations that still require NMEA 0183, Furuno offers the optional GP3-400-183-06 6 m pigtail cable. With that cable installed in place of the NMEA 2000 cable, the GP340 can output common 0183 navigation sentences including GGA, GLL, GSA, GSV, RMC, VTG and ZDA at a fixed 38.4 kbaud rate. The receiver uses either the NMEA 2000 cable or the NMEA 0183 cable at one time; it does not output both interfaces simultaneously. This distinction is important when planning a mixed old/new electronics refit.

Position Receiver vs. Heading Sensor

The GP340 supplies position, course-over-ground and speed-over-ground derived from GNSS, but it is not a satellite compass and does not provide the high-quality true heading data required by some advanced functions. Radar overlay, sophisticated autopilot behaviour and other heading-dependent applications may call for a dedicated heading source such as a Furuno SCX-series satellite compass. Buyers building a complete navigation system should therefore consider whether they need position only or both position and precise heading.

Installation and Environmental Use

The receiver can be surface mounted or fitted to a standard marine antenna pole/pipe. Install it where it has a broad, unobstructed view of the sky and where nearby transmitting antennas, large metal structures and sources of electrical interference will not compromise reception. Furuno specifies 12–24 VDC operation through the data/power connection, an operating temperature range of approximately -25°C to +70°C, and IPX6 water resistance, making the unit suitable for exposed marine installation when mounted according to the manufacturer’s instructions.

What’s in the Box

• GP340 GNSS/SBAS receiver
• 6 m GP3-400-N2K-06 NMEA 2000 cable assembly
• Surface/deck-mount adapter and associated installation hardware
• Pipe/pole-mount adapter for standard 1"-14 mounting
• Cable side-exit hardware / mounting components as supplied
• Owner’s and installation documentation

Specifications

• Product type: External GNSS/SBAS position receiver
• GNSS channels: Multi-channel receiver; Furuno technical literature lists a 75-channel GNSS core
• Supported GNSS: GPS L1/L5, GLONASS L1, Galileo E1/E5, QZSS L1/L5, BeiDou B1/B2
• SBAS: WAAS, EGNOS, MSAS, GAGAN
• Position update: Up to 10 Hz
• Position performance: Approx. 1 m CEP; less than 3 m at 95% under specified conditions
• Cold start: Less than approximately 60 seconds
• Hot start: Approximately 1 second
• Maximum tracking speed: 999 knots
• Standard interface: NMEA 2000 with supplied 6 m cable
• Optional interface: NMEA 0183 using optional GP3-400-183-06 cable
• NMEA 0183 output: GGA, GLL, GSA, GSV, RMC, VTG, ZDA at 38.4 kbaud
• NMEA 2000 network load: 1 LEN
• Power: 12–24 VDC; approximately 30 mA at 12 V / 20 mA at 24 V
• Approx. receiver size: 98 mm diameter x 75 mm high
• Mounting: Surface/deck or standard 1"-14 pole/pipe mount
• Water resistance: IPX6
• Operating temperature: Approx. -25°C to +70°C
• Important: Position receiver only; not a true-heading satellite compass