FAQs & Tutorials Compasses, Electronics & Navigation

Compasses, Electronics & Navigation
  • My boat has a steel or ferrocement hull. Which compass should I choose?

    No compass can answer this specific requirement alone. It is necessary to call for the services of a professional compass adjuster who will set up a compensation system relevant to your boat.

  • My compass has a bubble. What should I do?

    The cell of the Plastimo compasses is designed to be completely fluid filled. If you see a permanent bubble, in a temperature range from –20° to +60°C, it means that your compass is leaking (as the fluid tends to evaporate, you may not have noticed the leak).

    Contact our after-sales department for advice.

  • The dome of my compass is damaged. Is it possible to repair or replace it?

    Replacing the dome is not possible. If the dome is scratched, you can smooth out the scratches by using products such the Plastimo SEA 77 rubbing cream and the polish.

    If the dome turns whitish, rinse it with fresh water and soap. If rinsing is not sufficient, proceed as described above, using a polish.

  • Minimal care to ensure years of reliable service…

    Rinsing your compass with fresh water and soap is the only minimal requirement. Solvants, abrasive or corrosive cleaners must absolutely be banned.
    Sunlight and cold temperatures accelerate the ageing process of materials. Do not hesitate to protect your compass in all seasons (either by taking it down for wintering, or by protecting it with a hood or even a simple cloth which inhibits UV-rays).

  • Lighting does not work any longer. What should I do?

    Simply replacing the bulb is the answer in most cases.
    Still, you should also check the connection clamping and make sure that there is no corrosion on the wires or the connector.

  • Some water is leaking along the bulkhead, underneath the compass.

    Make sure you drilled the hole at the exact cut-out dimension, as instructed on the drilling template supplied with the compass. Check that the mounting surface is perfectly even and flat.

    Some compass models are supplied with a gasket for watertightness ; check that the gasket is properly positioned and that the light wire is correctly fed through the appropriate hole.

  • My compass does not indicate the right course. Why?

    If you notice a course discrepancy of exactly 180°, the answer is probably that you are not reading your compass properly. With a flat card, the lubber line marks your heading at the back of the compass. With a conical or cylindrical card, course reading is done on the front of the compass.

    On the Contest 101 model, the rear lubber line allows reading from inside the cabin.

    For any other course discrepancy, the compass deviation should be minimised :

    • Make sure that your compass is mounted at least 70 cm from objects generating local magnetic fields (compass, fire extinguisher, loudspeaker, electric wires and equipment, metallic parts of steering system, camera, tools, analogic instruments…) and at least 1 metre away from the main engine and the windscreen wipers motor.
    • Deviation correction :
      If deviation is no more than 7° : simply draw a deviation table assessing the error, and keep it for future reference.


    If deviation is between 7 and 20° : we recommend that you have your compass compensated as a start, and then draw a deviation table. The compensation procedure is a delicate operation and should ideally be carried out by a professional compass adjuster.

  • I plan to sail in a geographical area which is different than the zone my compass is designed for. Can I use my current compass?

    All our compasses are balanced manually : with a standard procedure for Zone A* models, and using a specific magnetic field simulator for all other area compasses. Balancing the compass consists in adjusting the card so that it is perfectly horizontal. If you sail to far away from the area for which your compass was originally balanced, the card will dip and the precision can be affected by a few degrees. For a long passage in a different zone, the acquisition of a compass specifically balanced for that area is a wise investment.


  • T.50 / T.56 & C.56 : How can I connect my GPS?

    Please refer to you manual or to the schematic below:

    Number  Color  Function
    1  Black   Ground: - power in, NMEA ground. 
    2  Brown   Ignition_On
    3  White  NMEA 1 Out
    4 Blue  NMEA 1 In 
    5  Red  + power in, 12 to 34 V DC
    6  Orange   NMEA 2 Out
    7  Yellow   NMEA 2 In
    8  Green   External alarm 


  • NAVTEX feature

    How NAVTEX feature works

    Plotter doesn’t try to communicate with NAVTEX receiver until you enter the NAVTEX menus and execute “Reload all” menu, which means, if you want to see recent NAVTEX messages, you have to execute “Reload all” first. When you execute “Reload all” menu, plotter tries to communicate with the NAVTEX receiver. It gets the NAVTEX messages from the NAVTEX receiver and saves Maximum 50 recent messages to internal NAND memory. 2MB NAND memory space is reserved for it. Once a message is saved to NAND memory, it’s not deleted until you execute “delete” or a more recent message is arrived by “Reload all” menu execution.

     Communication between plotter and NAVTEX receiver

    • Port setup they communicate through NMEA-0183 port of plotter and INS port of NAVTEX receiver. You have to setup the configuration of the port, like baud rate, parity, data bit and stop bit, as the same for the both side. Commercial NAVTEX receiver’s INS port is set as baud rate (4800, 9600 or 38400), parity (none), data bit (8) and stop bit(1) usually, and you should be able to change it as well.
    • Protocol: they communicate according to IEC 61162 format and use sentences as “NRX”, “NRM”. “CRQ”.

     NAVTEX Menu

    • Reload all: Plotter communicates with the NAVTEX receiver. It gets the NAVTEX messages from the NAVTEX receiver and updates the NAVTEX screen on the plotter. (Max. 50 recent messages)
    • Delete: deletes selected message from the screen and NAND memory.
    • Delete all: All the messages are deleted the screen and NAND memory.
    • View message: show the entire contents of the selected message on a new window for a long message


    Commercial NAVTEX receivers having INS port would be compatible with our plotter for the feature.

    Can you please explain what is INS port (is it serial port?)

    Yes it is serial port (mainly RS-422). Integrated Navigation System is designed to exchange Navtex data between NAVTEX and other devices such as ECDIS and Navigator. The NAVTEX will send its data via this INS port, or receive some request from NAVIGATORs.

    Does this mean our plotter will not be compatible with active antenna?

    No. If the active antenna (active antenna is a NAVTEX receiver) has a NMEA-0183 port, it would be compatible with it.

    I need a list of compatible Navtex device on the market. Can you please send me one with some reference?

    Regarding the NAVTEX receiver, we tested two NAVTEX receivers and test was good. As you know, a NAVTEX receiver follow IEC61162 communication format and NRX, NRM & CRQ sentence then it will not have any problem. 

  • Can I connect a fuel sensor to my Advansea plotters?

    Yes. You can connect a NMEA 2000 fuel sensor directly to your Advansea Plotter. You will find all the parts you need just below and how to connect it. List of the references you need if you just want to connect the fuel sensor to your plotter:

    • NMEA 2000 fuel senor
    • T connector for NMEA 2000 network (reference 58499)
    • Female termination resistor for NMEA 2000 network (reference 58501)
    • Advansea NMEA 2000 cable (reference 58494)

    Please note that we did test the Garmin fuel sensor (GFS 10).

  • Which geodesic system does the TR-200 use for GPS position?

    I did set my GPS onto WGS 84. If I send position from PRO AIS to GPS using NMEA and connect another GPS with a single AIS receiver (to see the send position via TR-200) the position between our AIS signal and boat is not the same (shift is up to 0.02NM).

    The GPS uses WGS-84, and it is important the chart plotter uses the same geodesic system and that any other GPS connected to the chart plotter also uses WGS-84. It is normal to see some small differences between two GPS receivers in the same location due to antenna spacing, GPS accuracy and the different algorithms GPS manufacturers use for positioning. NB. The GPS receiver in our Class B has been tested by BSH in Germany for position accuracy as part of the AIS type approvals. 

    The only point I have now is on the button status blue LED with internal switch… If I press the switch to turn the transceiver OFF, the blue LED stays “ON” even after release the button and it turn OFF only when pressing this same button again… This is not the same way than for external switch… Is the system supposed to run like this?

    The blue LED indicates that the unit is in silent mode, so it stays illuminated whilst the unit is in silent mode. The switches operate in a slightly different way:

    • the internal switch 'toggles' the status of silent mode each time you press it
    • the external switch enables silent mode when short circuit, and you should use a toggle type switch (not a momentary switch) with this option.

    If the blue LED is not illuminated, then silent mode is not enabled and the unit will continue to transmit. 

  • AIS way of working

    The reason that you have to wait for the Class B to transmit is down to the way that AIS devices automatically manage themselves on the AIS network. Each minute is divided into 2250 time slots and each AIS device needs to listen to the existing AIS transmissions before deciding when it can transmit. Class B AIS devices like the TR-210 operate on a CSTDMA system, (Carrier Sense Time Division Multiple Access). This means that they give priority to transmissions from Class A equipped vessels. When a Class B is switched on, it first has to receive a GPS signal and then it must listen to the slot map to figure out when it can transmit. When it is moving slower than 2 knots, then it will transmit once every 3 minutes. If it is moving faster than 2 knots, then it will transmit every 30 seconds. All of this means that potentially, once it has a GPS fix, a Class B may have to wait up to 6 minutes to be able to transmit (though usually it's a lot quicker!).

  • AIS TR-210

    We occasionally hear from customers who have experienced unit failures when a unit has been powered by 12/24V whilst also being connected to a PC/Laptop. The reason for this is that the USB port built into the Cobalt/NEON II is not isolated from the vessel power supply, VHF antenna ground or GPS antenna ground. This being the case, we advise you to observe the following procedures when connecting the USB port to avoid grounding problems;

    • If the computer is permanently installed on the vessel and/ or electrically connected to any other vessel equipment, including power supplies, it is recommended that connection is made using NMEA0183 or NMEA2000 connections.   These benefit from being specifically designed for use in the marine environment and provide isolated and robust communication between your devices
    • If a battery powered laptop is being used then it is recommended to switch off the computer, connect the USB cable, then switch on the laptop.  This will help to ensure that all equipment grounds are correctly referenced before use, minimising any risk of equipment damage.
  • SD user card

    Do you know if the SD User Card, which can be used to save/load Waypoints, has a capacity limit?

    We have done some experiments with this, because we had some complaints from customers.

    We found:

    SD Card 256Mb -> Functions Ok

    SD Card 1Gb -> Functions Ok

    SD Card 2Gb -> Does not function, instrument displays the message:

    "Required file has been not found on the current device" when trying to format the SD Card.

    So our conclusion is that a User Card with a capacity till 1 GB can only be used.

    Do you know more about this?

    Regarding SD card compatibility, our GPS are fully compatible with all SD card versions if they are correctly formatted. I mean that we need to format them using FAT 32 system with 512bytes sectors under windows. This is not default setting of Windows and you need to change these settings (if possible under your windows version). If not, you need to use SD HC card which are already in 512bytes sectors. I know that you can easily select 512bytes sectors format using Vista and 7… but not always under XP… You can try using DOS with this command: Format E: /FS:FAT32 /X /A:512 and set no name to the formatted volume (check if the command is OK, I cannot really remember).. Easiest thing to do is to use only SD HC cards…

  • DSC OUTPUT on FX-400 : Does it have an NMEA 0183 DSC output?

    I have one question regarding FX-400. Does it have an NMEA 0183 DSC output? I took a look at the MT 500 manual and saw NMEA output for PC/DSC printer. Can you explain what for and how it works?

    Description of NMEA Data Cable on manual says "Pin 3 & 4 reserved for DSC / Printer interface". Yes, FX-400 has NMEA 0183 DSC output. You can see the received DSC data on the connected DSC capable plotter. Also you can monitor the transmitted / received DSC data on your Windows PC using Hyper Terminal software.

  • Navman / Advansea instruments compatibility

    Advansea  Navman  Sensor compatibility Comments 
    Speed S400 ADVANSEA Speed 3100 NAVMAN Yes  
    Depth S400 ADVANSEA Depth 3100 NAVMAN Yes  
    Multi S400 ADVANSEA Multi 3100 NAVMAN Yes  
    Wind S400 ADVANSEA Wind 3100 NAVMAN No (*) (*) User can keep the existing cable between the bottom of the mast and the display.
    Wind-a S400 ADVANSEA Wind 3150 NAVMAN No (*) (*) User can keep the existing cable between the bottom of the mast and the display.
    Speed S400 ADVANSEA Speed 100 NAVMAN No (**) (**)  Need to change the sensor (ref 42285). Customer can keep the thru-hull.
    Depth S400 ADVANSEA Deph 100 NAVMAN Yes  
    Multi S400 ADVANSEA Multi 100 NAVMAN Yes (**) (**)  Need to change the sensor (ref 42285). Customer can keep the thru-hull.
    Wind S400 ADVANSEA Wind 100 NAVMAN No