MD86HCU Touch Screen Heading Comparator Unit

Touch Screen Heading Comparator which monitors and compares up to four heading sources, with off-course alarm.

SKU: F086002 Category:


The MD86HCU Heading Comparator Unit monitors and compares the headings of up to four compasses with a NMEA heading output. Compass types include: Gyro compass, GPS Compass, Transmitting Magnetic Compass (TMC) and Electromagnetic Compass (EMC). The MD86HCU has an integrated Heading Monitor (Off-Course Alarm) with easy to set user controls.

  • Two or more compass headings may be compared and an alarm given if the headings diverge by more than a pre-set amount (compass divergence alarm)
  • Ship’s Heading may be monitored and an alarm given if this exceeds a pre-set bandwidth (off-course alarm)
  • Any one of the input headings may be selected for onward re-transmission to the ship’s compass repeaters

The unit is configured from the front panel LCD Touchscreen using an intuitive graphical user interface. Compact and rugged, the MD86HCU offers a compass monitoring solution for locations where the available space is limited and may be either bulkhead or panel mounted. Finished in jet black to complement other marine navigation equipment.
The MD86HCU Heading Comparator Unit from MARINE DATA: Flexible in application, easy to install and simple to maintain.


  • Four NMEA 0183 heading inputs; Selectable NMEA compass heading output
  • Compass Comparator displays Compass Divergence; Integrated Heading Monitor displays Heading
  • Main and Emergency power supplies; with monitoring of both
  • External alarm loop circuit for interfacing to ship’s alarm panel
  • Automatic selection and prioritisation of NMEA heading data types: THS and HDT (true), HDG (magnetic + variation)
  • Easy to use colour LCD touchscreen with intuitive GUI
  • Fail-Safe feature directs sensor to output in the unlikely event of a system failure


  • Heading Comparator – Compares the headings of two or more compasses and sounds an alarm if the error exceeds a pre-set value and duration
  • Heading Monitor – Monitors Heading of Compass selected for re-transmission and sounds an alarm if the differs from the Set Heading by more than a pre-set limit and for a pre-set time
  • Fulfils the mandatory IMO requirement for comparing the headings of 2 gyro compasses, where fitted


  • MD94HDU Heading Distribution Unit (supplied with the MD86HCU)
  • THD (Transmitting Heading Device) Systems
  • MARINE DATA Compass Repeaters


  • Power Supply: 24 V dc (18-32 V) 10 W main and backup supplies
  • Data Inputs:
    • 4x NMEA 0183 (IEC61162-1) for Compass Data Input
    • 3x NMEA 0183 for Additional Functions
    • 3x Digital Input for connection to Compass Device Alarm Output 1x Digital Input for external Alarm Acknowledge switch
    • 1x Digital Input for Additional Function
  • Data Outputs:
    • 1x RS422 NMEA 0183 Compass Data Output as received from the selected Compass Data Input for re-transmission to Repeaters
    • 1x RS422 NMEA 0183 Supplementary Data Output (option)
    • 3x RS422 output for additional functions
    • 2x Digital Output (1 A 60 V) for Remote Alarm Indication / Echo
    • 1x Front Panel USB A socket, Log Files and Software Maintenance
  • Data Sentences:
    • THS, HDT, HDG (with Variation); in order of priority, 4800 / 9600 / 19200 / 38000 Baud; auto-selecting
    • NMEA 0183 ‘THS’, ‘HDT’ or ‘HDG’ (including variation) sentence must be present in data from Compass. Other sentences may be present and will be re-transmitted
  • Cable: 1.5 m multi-core data cable to Junction Box MD94HDU


  • Performance: Heading Displays and Alarm Calculations to 0.1°
  • Display: LCD touch screen GUI (640 x 480 pixels) 5.7” diagonal 4:3 aspect
  • Illumination: Backlit; touchscreen controlled
  • Error Indication: Audible and visible for loss of valid data & gyro hardware fault
  • Alarms: Off-Course: Audible and visible indications
    • Compass Divergence: Audible and visible indications
    • Fail-Safe activated: Visible indicator and external alarm loop
    • Power supply failure: Audible and visible indications
    • External alarm loop circuit to ship’s alarm panel
  • USB Port: Upload software updates; download alarm log


  • Weight: 1.5 kg
  • Dimensions: H166mm;W200mm; D81mm Fascia 144 x144 x 6 mm
  • Mounting: Panel or Bulkhead Mounted
  • Connections: 1x 37-way D-sub; 1x 15-way D-sub; 1x M4 Earth Stud
  • Construction: Aluminium alloy enclosure
  • Finish: RAL9005 Jet Black; fine texture


  • IP rating: IP54
  • Operating Temp: -15°C to +55°C
  • RoHS: Compliant
  • Compass: Safe Distance 50 cm


  • Conforms to: IEC 60945; IEC 61162-1; ISO 62288


  • Supplied: Panel Mount Kit; MD94HDU Junction Box; 37-way data cable
  • Option: 15-way cable for extended functionality
  • Accessory: Bulkhead mounting bracket kit
  • Accessory: Remote Alarm MD86ALM
  • Accessory: Remote Dimmer

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