The document specifies requirements for a compass to supplement an ADCP (acoustic Doppler current profiler). The compass must be a flux-gate compass accurate to 0.5 degrees with 0.2 degree repeatability and 0.1 degree resolution. It must operate reliably between 0-60 degrees Celsius, output data in NMEA-0183 format at 1 Hz, and come with a manual and sturdy transport case. The compass is intended to reference ADCP readings to directions for use on boats away from ferromagnetic materials.

1. 10.023 COMPASS
Approval Date: 20 May 1998
Reviewed on : 23 October 2007 Version: 1
Equipment Specification: COMPASS Version 1 10.023-1/2
Purpose
The compass is an optional supplement to the ADCP to reference the ADCP readings to East-
West and North-South direction. It is to be installed externally, e.g. in a mast, away from
ferromagnetic material.
Conditions & Requirements
• The flux-gate compass shall be of such a design that it operates reliably and accurately
under the prevailing flow and environmental conditions.
• The compass shall be easy to operate and maintain.
• The compass shall be supplied with the accessories as needed for effective use.
• All external materials of the compass shall be non-corrosive.
• An operator’s manual, related to the type and model of the compass, shall be part of the
delivery.
• The electrical connections shall be of a reliable and sturdy construction.
• The compass and accessories shall be supplied in a sturdy transport case.
• The North -direction of the compass sensor shall be parallel with the longitudinal axis of the
boat.
• The installation of the sensor at the bow shall be such that the sensor can easily be
removed and re-installed with the same alignment.
• The compass shall have calibration functions. The calibration shall compensate for local
magnetic conditions and for the magnetic effects of the boat, including engine, generator
on the compass reading.
• The data shall be delivered by serial (RS232) connection either directly to the data
acquisition PC or to a ‘deck-box’ (depending on ADCP type and make).
• The compass data format shall comply with NMEA-0183 specification.
Specifications
The purchaser may execute his judicious discretion in the choice of configuration and
options.
type flux-gate compass
accuracy 0.5°
repeatability 0.2°
resolution 0.1°
tilt angle 15°
power supply 12 VDC or 24 VDC
output data format NMEA-0183 compliant
serial port RS 232
output update frequency 1 Hz
enclosure compliant to IP65
operating temperature 0 to 60°C
operating humidity 100 %
Accessories
• manual

2. 10.023 COMPASS
As per HP-I
Approval Date: 20 May 1998 Version: 1
Equipment Specification: COMPASS Version 1 10.023-2/2
Purpose
The compass is an optional supplement to the ADCP to reference the ADCP readings to East-
West and North-South direction. It is to be installed externally, e.g. in a mast, away from
ferromagnetic material.
Conditions & Requirements
• The flux-gate compass shall be of such a design that it operates reliably and accurately
under the prevailing flow and environmental conditions.
• The compass shall be easy to operate and maintain.
• The compass shall be supplied with the accessories as needed for effective use.
• All external materials of the compass shall be non-corrosive.
• An operator’s manual, related to the type and model of the compass, shall be part of the
delivery.
• The electrical connections shall be of a reliable and sturdy construction.
• The compass and accessories shall be supplied in a sturdy transport case.
• The North -direction of the compass sensor shall be parallel with the longitudinal axis of the
boat.
• The installation of the sensor at the bow shall be such that the sensor can easily be
removed and re-installed with the same alignment.
• The compass shall have calibration functions. The calibration shall compensate for local
magnetic conditions and for the magnetic effects of the boat, including engine, generator
on the compass reading.
• The data shall be delivered by serial (RS232) connection either directly to the data
acquisition PC or to a ‘deck-box’ (depending on ADCP type and make).
• The compass data format shall comply with NMEA-0183 specification.
Specifications
The purchaser may execute his judicious discretion in the choice of configuration and
options.
type flux-gate compass
accuracy 0.5°
repeatability 0.2°
resolution 0.1°
tilt angle 15°
power supply 12 VDC or 24 VDC
output data format NMEA-0183 compliant
serial port RS 232
output update frequency 1 Hz
enclosure compliant to IP65
operating temperature 0 to 60°C
operating humidity 100 %
Accessories
• manual