BS EN 61162-3-2008 pdf download.Maritime navigation and radiocommunication equipment and systems Digital
interfaces Part 3: Serial data instrument network.
This part of IEC 61162 is based upon the NMEA 2000 standard. The NMEA 2000 standard contains the requirements for the minimum implementation of a serial-data communications network to interconnect marine electronic equipment onboard vessels. Equipment designed to this standard will have the ability to share data, including commands and status, with other compatible equipment over a single signalling channel.
Data messages are transmitted as a series of data frames, each with robust error check confirmed frame delivery and guaranteed latency times. As the actual data content of a data frame is at best 50 % of the transmitted bits, this standard is primarily Intended to support relatively brief data messages, which may be periodic, transmitted as needed, or on-demand by use of query commands. Typical data includes discrete parameters such as position latitude and longitude, GPS status values, steering commands to autopilots, finite parameter lists such as waypoints, and moderately sized blocks of data such as electronic chart database updates. This standard is not necessarily intended to support high-bandwidth applications such as radar, electronic chart or other video data, or other intensive database or file transfer applications.
This standard defines all of the pertinent layers of the International Standards Organisation Open Systems Interconnect (ISO/OSI) model, from the application layer to the physical layer, necessary to implement the required IEC 61162-3 network functionality.
This standard defines data formats, network protocol, and the minimum physical layer necessary for devices to interface. SOLAS applications shall employ redundant designs (for instance dual networks, redundant network interface circuits) to reduce the impact of single point failures. The NMEA 2000 standard provides the fundamental tools and methods to support redundant equipment, buses and messaging. Specific shipboard installation designs are beyond the scope of this standard, however some guidance is given in Annex A.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies, For undated references, the latest edition of the referenced document (including any amendments) applies.
IEC 60945, Maritime navigation and radiocommunication equipment and systems — General requirements — Methods of testing and required test results
ISO 11783 (all parts). Tractors and machinery for agriculture and forestry — Serial control and communications data network
ISO 11783-3, Tractors and machinery for agriculture and forestry — Serial control and communications data network — Part 3: Data link layer
3.1.7
default operation
operation or settings that exist when standard equipment is first shipped from the manufacturer
3.1.8
device
a product or equipment which, through a node, is connected to an lEG 61162-3 network
3.1.9
gateway
device that joins a network to another network or system
3.1.10
interframe space
bit field that separates data frames from preceding frames
3.1.11
level A devices
support the ISO transport layer and the complete set of network management parameter groups
3.1.12
level B devices
support address claim. ISO request PGN. and the product information parameter group
3.1.13
listen only device
device on the network that receives messages but does not participate in bus activity
NOTE This device cannot send any frames on the network (data, error, or acknowledge),
3.1.14
load equivalency number
a node’s power rating reported in units of network load
3.1.15
message
consists of one or more data frames, as specified in this standard, that contain the parameter group information to be communicated from a network address
NOTE A message contains the message priority code, parameter group number, destination network address, source network address, and data fields. The destination network address may be a specific address or global.
3.1.18
node
a physical connection to the network
NOTE A node may have more than one network address, see virtual nodes.
3.1.19
node power
power supplied from the network
3.1.20
parameter group (PG)
set of associated variables, commands, status, or other information to be transmitted on the network
3.1.2 1
parameter group number (PGN)
an 8-bit or 16-bit number that identifies each parameter group
NOTE The parameter group number (PGN) is analogous to the three-character sentence formatter in IEC 61162.1. By definition, parameter groups identified by 16-bit parameter group numbers are broadcast to all addressee on the network. Parameter groups identified by B-bit parameter group numbers may be used to direct data for use by a specific address.
3.1.22
receiver
recipient of a message if the bus is not idle and the device is not a transmitter
3.1.23
router
device that joins two network segments with the same network protocol
NOTE On each side of a router address space, data rate and physical media may differ
3.1.24
transmitter
originator of a message
NOTE The unit remains a transmitter until it loses arbitration or until the bus becomes idle.
3.1.25
virtual nodes
functional entities within a device that share a physical connection to the network.BS EN 61162-3-2008 pdf download.