GB/T 43525-2023 Ships and marine technology - Navigation and ship operations - Electronic inclinometers
1 Scope
This document specifies the performance requirements, methods of testing and test results of electronic inclinometers, in addition to the general requirements contained in IMO Resolution A.694 (17) and is associated with IEC 60945.
It applies to the electronic inclinometers required by IMO resolution MSC.363 (92).
The electronic inclinometers provide information about actual heel angle, roll amplitude, roll period to support decision-making process on board in order to avoid dangerous situations, in stability (see Annex A), as well as to assist in maritime casualty investigation. The electronic inclinometers are mainly composed of a set of sensors, a signal processor, a display, an input device and an interface to other systems.
It does not apply to the electronic inclinometers installed for purposes which are outside the scope of this document, e.g. monitoring of cargo status.
Where a requirement in this document is different from IEC 60945, the requirement in this document takes precedence.
Note: The requirements of IMO Resolution MSC.363 (92) are applicable in this document, the resolution and paragraph numbers are indicated in brackets.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced documents (including any amendments) applies.
IEC 60945 Maritime navigation and radiocommunication equipment and systems - General requirements - Methods of testing and required test results
Note: GB/T 15868 - 1995 Shipborne radio equipment forming part of the GLOBAL MARITIME DISTRESS AND SAFETY SYSTEM and Marine navigational equipment - general requirements, methods of testing and required test results (IEC 60945 : 1994, IDT)
IEC 61162-1 Maritime navigation and radiocommunication equipment and systems-Digital interfaces - Part 1: Single talker and multiple listeners
IEC 61162-2 Maritime navigation and radiocommunication equipment and systems-Digital interfaces - Part 2: Single talker and multiple listeners, high-speed transmission
Note: GB/T 31843.2 - 2019 Maritime navigation and radiocommunication equipment and systems - Digital interfaces-Part 2 : Single talker and multiple listeners - High-speed transmission (IEC 61162-2 : 1998, IDT)
IEC 61924-2 Maritime navigation and radiocommunication equipment and systems - Integrated navigation systems - Part 2: Modular structure for INS-Operational and performance requirements, methods of testing and required test results
IEC 62288 Maritime navigation and radiocommunication equipment and systems - Presentation of navigation-related information on shipborne navigational displays - General requirements, methods of testing and required test results
IMO resolution MSC.191 (79) Performance standard for the presentation of navigation-related information on shipborne navigational displays
IMO resolution MSC.252 (83) Performance standards for Integrated Navigation Systems (INS)
IMO MSC.302 (87) Performance standards for bridge alert management (BAM)
IMO MSC.363 (92) Recommendation on performance standards for electronic inclinometer
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
actual heel angle
momentary angle of roll referenced to a levelled ship to port or starboard side
[Source: IMO MSC.363 (92), 3.1]
3.2
analogue type display
display (3.4) that shows actual heel angle (3.1), roll amplitudes (3.7) and roll peak hold values (3.9) in a continuous way, such as by means of an arrow pointer and graduated scale
3.3
digital type display
display (3.4) that shows actual heel angle (3.1), roll amplitudes (3.7) and roll peak hold values (3.9) in the form of numbers
3.4
display
means by which the roll behaviour of the ship and the state of the electronic inclinometer system are presented to an observer
3.5
inspection equipment
equipment for testing the performance of the electronic inclinometer
3.6
reset function for roll peak hold value
function for resetting roll peak hold values (3.9) to zero and for recording reset date (month, day and year) and time
3.7
roll amplitude
maximum values of heel angle to port or starboard side
[Source: IMO MSC.363 (92), 3.1]
3.8
roll period
time between two successive maximum values of heel angle on the same side of the ship
[Source: IMO MSC.363 (92), 3.1]
3.9
roll peak hold value
maximum values of roll amplitude (3.7) to port or starboard side from the last reset
3.10
rolling
motion around the longitudinal axis of the ship
Note: Positive roll is starboard down.
[Source: IMO MSC.363 (92), 3.1]
3.11
zero crossing method
way for measuring wave period by using a zero crossing which is a point where the sign of a measured value (roll angle) changes
Example: From positive to negative.
4 Requirements
4.1 General
Users of this document shall note that while attempting to implement the requirements, they shall ensure compliance with such statutory requirements, rules and regulations so as to be applicable to various ships.
4.2 Functionality
[IMO MSC.363 (92), 1.2] The electronic inclinometers shall in a reliable form
a) determine the actual heel angle with the required accuracy,
b) determine the roll amplitude with the required accuracy,
c) determine the roll period with the required accuracy,
d) present the information on a bridge display, and
e) provide a standardized interface to instantaneous heel angle to the voyage data recorder (VDR).
4.3 Information
4.3.1 Actual heelangle and roll amplitude
[IMO MSC.363 (92), 4] Electronic inclinometers shall be capable of measuring the actual heel angle and determining the amplitude of the rolling oscillation of the ship over a range of ±90°.
4.3.2 Roll period
[IMO MSC.363 (92), 5] Electronic inclinometers shall be capable of measuring the time between the maximum values of the rolling oscillation and determining the roll period over a minimum range of 4s to 40s.
If enough precision is not attained, the period may be measured by the “zero crossing method”.
4.3.3 Roll peak hold value
Electronic inclinometers may optionally record the roll peak hold values on both sides and present them on any kind of display.
If optional recording of the roll peak hold values is provided, electronic inclinometers shall have a mean of manually resetting the roll peak hold values by a single operator action.
If necessary, the following sentences may be provided for the reset of roll peak hold value:
$-TXT,01,01,01,EI_RPHVReset_yyyy_mm_dd_o0_nn_ss*hh (see IEC 61162-1)
