User manual LOWRANCE NMEA 2000 NETWORKS INSTALL GUIDE

[. . . ] 988-0154-172 NMEA 2000 Networks General Information NMEA 2000 is a communication bus network specifically designed for boats. This is an industry standard developed by the National Marine Electronics Association(NMEA). To help you get the most out of this technology Lowrance has introduced a line of products that can communicate over a NMEA 2000 network. This instruction sheet outlines the basics of what it takes to create a NMEA 2000 network. [. . . ] You should never use more than 15' (about 5 meters) of extension cable between a device and the network backbone. Building a LowranceNET NMEA 2000 Network In 2005, the original equipment manufacturers (OEM) began installing NMEA 2000 networks as standard equipment in new boats. If your boat does not have an OEM-installed NMEA 2000 network you will have to install your own. This instruction sheet will explain how to install a LowranceNET NMEA 2000 network using cables available from LEI. If you can grasp a few essential concepts you can design a network to fit your needs and keep it running smoothly. Power In order for a NMEA 2000 network to operate the bus must be connected to a switched power source (a power source that you can turn on and off ­ generally a switch on your boat's accessory panel). If your boat came with a NMEA 2000 bus it should already be connected to a switched power source that draws from the boat's battery. To confirm how the bus was installed, consult your boat dealer or manufacturer. · No matter how large or small the network, no matter how many devices are sharing information along it, a NMEA 2000 network must be connected to a 12-volt power source to operate. If you are only running a display unit and an LGC-2000 on the mininetwork as described earlier you will still have to connect the display unit's NMEA 2000 Power cable to a switched power source in order to power the network. 7 · Always use a switched power source for your NMEA 2000 bus. Do not connect the NMEA 2000 Power cable directly to your boat's battery. Many manufacturer-installed networks use one of these alternate power sources. If your network already includes either of these power sources do not connect the NMEA 2000 power cable of any of your GPS or sonar display units. OEM factory installations typically use a Power Node to supply power to the network bus. The red and black leads are connected to a switched power source, allowing the user to turn off power to the bus. WARNING!If you connect multiple power sources to a NMEA 2000 network you could cause severe damage to the network, attached devices and your boat!Terminators In order for it to work properly, a NMEA 2000 network needs to be terminated with either a single 60-ohm terminator or two 120-ohm terminators. The most common and preferred setup uses two 120-ohm terminators ­ one at each end of the bus. This must be used if you intend to use three or more devices on the bus. 9 If you have an LGC-2000 you have seen the small plug (with "60" imprinted in the plastic grip) that comes along with the T connector and extension cables. This little plug is as important to the mini-network as any of the other parts ­ this is the one 60-ohm terminator. If your boat came with an installed NMEA 2000 bus the terminators will already be attached. The terminators provide resistance necessary for devices to communicate along the network. This communication takes the form of electrical pulses sent out by the device transmitting information. [. . . ] So dramatically, in fact, that NMEA 0183 devices developed in the early days of the standard (NMEA 0183 ver. 1) are no longer compatible with NMEA 0183 devices developed recently (NMEA 0183 ver. In order to correct this and to prevent something similar happening again NMEA decided to adopt a new standard, NMEA 2000, which is a radical departure from the old NMEA 0183. The NMEA 2000 was planned from the beginning to be a consistent system capable of incorporating future growth. [. . . ]