Installation manual

Introduction

851--160116 / B

7.2 Connecting the course gyro

The Sonar Control Unit can be connected to a course gyro with

one of the following outputs (tick off for the type which will be

connected):

j 3--phase synchro signal See chapter 7.2.1

j 3--phase stepper signal See chapter 7.2.2

j Serial line (NMEA 0183) See chapter 7.2.3

Connecting a course gyro with synchro output

j First, get the specifications of the gyro to fill in the

following data:

SYNCHRO DATA SPECIFICATIONS LEGAL VALUES

OUTPUT VOLTAGE 20 to 220 VAC

FREQUENCY 50/60/400 Hz

GEAR RATIO 1:360/1:180/1:90/1:36

If it is difficult to find the specifications for the gyro, the output

voltage and frequency can be measured in the following way:

j The output voltage can be measured by an AC voltmeter

or by an oscilloscope on the reference output R1 & R2.

Notethat ifanoscilloscopeisused,thereferenceprobeon

the oscilloscope must not be connected to the mains

ground, and the measured peak to peak value of the

output voltage must be divided by 2 Ö2 to get the RMS

voltage.

j Fill the output voltage value into the table above.

j The frequency can be measuredby an oscilloscope on the

reference output R1 & R2. Note that the reference probe

on the oscilloscope must not be connected to the mains

ground.Calculatethefrequency1/T(Tisthetime forone

sine wave) and fill the result into the table above.

j If the gear ratio of the gyro output also is unknown, this

has to be tried out later when testing the readout of the

gyroontheSonarControlUnit.Insuchcase,setthegear

ratio to 1:360.

When connecting the gyro cable to the 15 pin D- connector, note

that each of the three phases S1, S2, S3 and the reference R1 has

three different connection pins, marked L (Low), M (Medium)

and H (High). These pins are used for different gyro output

voltage values as indicated for the connections below: