Introduction; General; Definitions And Abbreviations - JRC JLN-900 Installation And Instruction Manual

1 Introduction

1.1 General

This document describes the Sig. Distributor, which serves as an interconnection device
between speed logs, NWW-82/85 displays, indicators and other users, such as ARPA, auto-
pilots etc. IEC61162/NMEA serial signals and how to connect these cables are described in
document "IEC61162/NMEA0183 User Guide".

1.2 Definitions and abbreviations

The performance standard IMO MSC.191(79) states that standardized terms and definitions
shall be used. The speed logs have historically used the terms Bottom Track (BT) for Speed
Over the Ground (SOG) and Water Track (WT) for Speed Through the Water (STW) related
information. This document introduces the SOG and STW terms, but due to backward
compatibility and existing menu system, both terms exist.
Abbreviation
NMEA0183
STW
WT
WTL
WTT
SOG
BT
BTL
BTT
TRIP
TOTAL
Description
IEC61162-1 ed2 serial interface standard
Speed Trough the Water.
This is equivalent to Water Track (WT) speed (relative)
Water Track resulting speed or distance (relative)
Water Track Longitudinal and may refer to both
speed and distance
Water Track Transverse and may refer to both
speed or distance
Speed Over the Ground.
This is equivalent to Bottom Track (BT) speed (true)
Bottom Track resulting speed or distance (true)
Bottom Track Longitudinal and may refer to both
speed and distance
Bottom Track Transverse speed or distance
Trip distance counter
Total distance counter
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