Points North Ltd.

Marine Gyro Compass / Navigational & Communication Systems   Marine Electrical & Electronic Systems

SYNCHRO INTERFACE

910 SERIES

INTRODUCTION

This interface converts gyro synchro transmission to NMEA 0183 (or proprietary data) plus stepper or Furuno data. It has an additional NMEA input channel to back up the gyro with a magnetic compass.

Applications are used in the gyro installation, and minimising the interfacing required for radar, ecdis and heading displays.

The interface is a precision device, correct to 0.1 degree, and does not require alignment in the 1:1 mode.

The interface also converts other gyro ratios such as 90:1 in which case provision is made for an alignment keypad.

SPECIFICATION

INPUT 1:    Synchro, for nominal 115v ref 90v signals or nominal 26v ref 12v signals.

Specify on order. Other synchro voltages easily accommodated.

Frequency 40 to 550 Hz. Reference input is isolated by transformer.

The synchro phases have a common at centre of the three phases, connected to the power 0v. For 90 volt synchro the input is via 270K in series with each phase.

Other voltages scaled at R = 3 x v Kohm.

Ratio selected by jumper, and EPROM configuration.

Conversion accuracy 12 bits. Conversion rate 20 per second. Switches to use the NMEA 0183 input if synchro fails.

INPUT 2:    NMEA 0183 port. Programmed for all NMEA heading sentences input, plus Cetrek and Yokogawa data. Gyro data takes priority over magnetic input automatically.

OUTPUT 1: NMEA 0183, Cetrek, or Yokogawa 4800 baud data. NMEA sentence HEHDT,xxx.x,T cr lf as default.

Output rate default is 1 per second AND whenever heading changes, in order to keep to spirit of NMEA standard, and minimise data sent. Fixed data rates optional, and apply to Cetrek and Yokogawa data out.

5v CMOS limited 5 mA drive. NMEA 0183, RS422, RS232 compatible.

OUTPUT 2:    Three 5v CMOS drivers 5mA. For: Yokogawa 2400 baud data, or Furuno AD10 output, or 6 step per degree stepper output as standard.

POWER:         9 to 32v DC at 300mA.

HOUSING:     Duck Egg Green diecast box 222 x 146 x 55 mm for indoor bulkhead mounting.

FEATURES:   LEDs on data in and out and bicolour status led.

Power fail and program run watchdog circuit.

All connections lift-off terminal blocks.

RATIOS:         The EPROM is configured for 1:1 and 36:1 as standard.

Other ratios are 9:1, 10:1, 30:1, 90:1.

In these cases an alignment keypad is fitted on the lid of the box.

ALIGNMENT:When alignment is required it is suggested the interface is fitted near a heading display unit such as the 991 or 950 so that the NMEA 0183 heading output is easily monitored.

OPTIONS:      The baud rate is variable up to 33400.

The Interface can deliver RUDDER ANGLE data $ERRSA when fitted with the rudder angle EPROM.

A version is available for tracking radar synchro output.

VERSIONS:    The 910-D indicates it has a digital CMOS output at SK4.

The 910-A model has an analogue +/- 10volt output.