6-3
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 Description
NMEA0183 IEC61162-1 ed2 serial interface standard
STW Speed Trough the Water.
This is equivalent to Water Track (WT) speed (relative)
WT Water Track resultin
speed or distance (relative)
WTL Water Track Longitudinal and may refer to both
speed and distance
WTT Water Track Transverse and may refer to both
speed or distance
SOG Speed Over the Ground.
This is equivalent to Bottom Track (BT) speed (true)
BT Bottom Track resultin
speed or distance (true)
BTL Bottom Track Longitudinal and may refer to both
speed and distance
BTT Bottom Track Transverse speed or distance
TRIP Trip distance counter
TOTAL Total distance counter
To Next Page
Loading...