Why NMEA isolation is critical to your network

When designing DC-powered products for marine networks, isolation must be considered. It is not recommended to connect NMEA devices directly to a computer. Without some form of isolation, this practice opens up risks of ground loops that can damage both the NMEA device and the computer (we'll cover this later in the article). Although there are many electronic devices without insulation on due to cost reductions or the belief that an older version of the NMEA standard added to it, the general consensus is that isolation in DC-powered systems is wise and possibly decisive; is the reliability.

What is insulation and why is it important?

Insulation prevents the two the biggest problems that plague DC power systems and the devices on them; ground loops and ground potential differences. A ground loop occurs when between or multiple paths to the ground connection for the ship's DC battery supply are created. When these paths to ground are at different potentials, which is easy to do with DC-powered systems, the problems can range from intermittent communication problems to complete device damage.

Marine galvanic isolation prevents current from flowing between electrical circuits while still allowing data to be shared through optical, mechanical or electromagnetic methods. The galvanic isolation of the board gives the user confidence that ground potential differences and ground loops cannot occur and thus neither can the resulting damage.

A small ground potential difference can be seen as random data corruption, while a larger ground potential difference can prevent data communication completely. Öover time, depending onå the size of the potential voltage difference, any device without marine DC isolation will be damaged. If you are 80 nautical miles from land without GPS on; due to total error, your estimate of isolation will greatly increase!

Marine opto-isolators ("Optos") securely transfer data between two individually isolated circuits with the help of light. In most cases, they consist of an LED that converts electrical energy into light and a photosensor such as a phototransistor that converts light into electrical energy.

What does this mean?< /h4>

Most boaters will likely want to connect their NMEA devices to their computers at some point, but doing so is essential before to protect your onboard equipment. We always emphasize the importance of creating a reliable marine data network, where isolation must be considered. Depending on your network requirements, we have various options to securely connect your NMEA devices to your computer.

**NMEA 0183 to PC**

< p>We have observed some new PC connection cables on the market that does not offer any insulation. As this article has emphasized, connecting NMEA devices directly to a computer without isolation is absolutely not recommended. To ensure full protection for both the NMEA device and your computer, we recommend using something like USG-2, which has isolation both on the input and output, as well as a USB connection for easy connection to the on-board computer.

Another option for isolation for PC connection is Actisense OPTO-4, which provides isolation to the PC's input but not the output. If your computer does not have a serial port, you will need a USB to serial adapter.

NMEA 2000 to PC

Actisense NGX-1 is a NMEA 2000 to PC Gateway that Is it possible to easily transfer NMEA 2000 data from the NMEA 2000 network to a computer. NGX-1 USB variant is chosen in most scenarios (where the computer has a USB port) because it can be "plug and play," while fully isolated to prevent dangerous ground loops.

Here are some concrete reasons why NMEA isolation important for your network:

1. Prevent earth cycles and ground noise
   Isolation helps to prevent earth cycles and ground noise that can arise; when different devices in the network have different ground references. Grounding problems can lead to signal corruption and malfunction of connected devices. Isolation breaks the electrical connection between the ground references of different devices, thereby eliminating the risk of ground cycles.
   
   
2. Protection against electrical disturbances
   In marine and automotive systems, electrical disturbances can Aches and pains are common. Isolation helps protect the network and its devices from harmful electrical impulses and surges. This is especially important for repairing damage to sensitive electronics and such reliable communication.
   
   
3. Improve system performance
   Isolation helps to improve performance by minimize disturbances and noise in the network. Stable and interference-free signals enable fast and reliable communication between devices. This is particularly important to ensure that data is transferred correctly and in real time.
   
   
4. Preventing the ground loop
   The ground loop can riseå when there are several paths for current to circulate in a network. This can cause unwanted voltage drops and affect the performance of the devices. Isolation interrupts these loops and reduces the risk of problems that may arise; on because of them.
   
   
5. Improve the stability of the system
   A voltage isolation helps to maintain a stable voltage level; in the network. This is important to avoid variations that can affect the sensitivity and accuracy of the devices. A stable tension environment It is crucial to ensure that all devices work correctly and provide reliable information.