| Tweet |
Custom Search
|
|
|
||
 TM 55-1905-220-14-7
3-216. HEADING SELECTOR - MAINTENANCE INSTRUCTIONS (Cont).
The Heading Selector is used as an interface between a gyrocompass and steering control panel to
select the desired heading of the vessel. The gyrocompass transmits actual heading data to the Heading
Selector for comparing the actual heading data with the ordered head- ing data. If the actual heading and the
ordered heading are the same, there is no signal output from the Heading Selector. If the actual heading and
the ordered heading differ, the Heading Selector will produce a signal that will cause the rudder positioning
equipment to change the vessel's actual heading to its ordered heading.
Three-wire synchro data from the gyrocompass provides the heading information, and the same 115-volt,
400-hertz supply that powers the gyrocompass is needed for reference and illumination requirements.
The gyrocompass card is connected to a synchro which is excited by a 115-volt, 400-hertz supply. Three-
wire heading data is transmitted by this synchro to synchro B1 of the Heading Selector. The heading selector
card is connected to synchro B1 rotor so that for any reading of the gyrocompass card, the voltage induced in
synchro B1 rotor will be zero when the heading selector card is set to the same heading. When the heading
selector card and the gyrocompass card are on different headings, an error voltage is induced in synchro B2
rotor.
3-3321
|
||
|
||
