ISO 20673:2022 pdf – Ships and marine technology — Electric rudder angle indicators

ISO 20673:2022 pdf – Ships and marine technology — Electric rudder angle indicators.
Scope This document specifies the construction, performance requirements, methods of testing and required test results for electric rudder angle indicators required to comply with Clause 2.5.4, Regulation 19, chapter V, SOLAS 1974 (as amended, 2000). This document is associated with IMO Resolution A.694 (17) and IEC 60945. Where a requirement in this document is different from IEC 60945, the requirement in this document takes precedence. 2 Normative references The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 60945, Marine navigation and radiocommunication equipment and systems — General requirements — Methods of testing and required test results 3? Terms? and? definitions For the purposes of this document, the following terms and definitions apply. ISO and IEC maintain terminology databases for use in standardization at the following addresses: — ISO Online browsing platform: available at https:// www .iso .org/ obp — IEC Electropedia: available at https:// www .electropedia .org/ 3.1 rudder angle indicator remote device that indicates ship’s rudder angle and direction Note 1 to entry: An indicator system consists of a transmitter and a receiver (indicator). 3.2 analogue-type indicator indicator that shows the rudder angle in a continuous way, such as by means of an arrow pointer and a graduated scale 3.3 digital-type indicator indicator that shows the rudder angle in a discrete, alphanumeric way
5 Performance requirements 5.1 General The transmitter shall have sufficient capacity to satisfy the requirements specified in 5.2, 5.3 and 5.4 when all the connected indicators are operating simultaneously. The manufacturer should specify the capacity of connected indicators. 5.2 Calibration accuracy a) When the shaft of the transmitter is gradually rotated from the zero position to the maximum angle port and starboard, and the angles shown by the indicator are recorded every 5° of the rotation, the difference between the angles of the transmitter shaft and the corresponding value shown at the indicator shall be within 1,5 % of the maximum angle. b) In equipment where there is conversion into rudder scale, the minimum unit of angle shall be 0,1° and any value less than 0,1° shall be rounded up to 0,1° after conversion. c) In cases of wider-angle indication (such as 70°), the angles shown by the indicator may be recorded at every 10°. 5.3? Damping? efficiency When a voltage is suddenly applied while the transmitter shaft is approximately at half of the full-scale position and the indicator pointer is set to the zero position, the pointer shall come to reset to that position within 5 s or less. 5.4? Power? supply? fluctuation a) When the power supply fluctuations specified in 5.4 c) are applied, the performance required by 5.1 and 5.2 shall be maintained. b) After repeated makings and breakings, the designated performance shall be demonstrated without carrying out manual adjustments. c) When the rated voltage and frequency are subjected to the combinations of fluctuations, as given in Table 1, the designated performance shall be demonstrated.
6.2 Environmental test Unless otherwise stated in this document, all the tests shall be carried out according to the requirements of IEC 60945. The manufacturer shall determine which components of electric rudder angle indicators will be protected or exposed, as defined in IEC 60945. 6.3 Calibration test The calibration test shall be carried out in accordance with 5.2 and shall satisfy the requirements specified therein. 6.4 Damping test The damping test shall be carried out in accordance with 5.3 and shall satisfy the requirements specified therein. 6.5? Power? supply? fluctuation? test The power supply fluctuation test shall be carried out in accordance with 5.4 and shall satisfy the requirements specified therein. 6.6 Alert test If the equipment under test is capable of raising an alert, confirm using documented evidence that the equipment complies with IEC 62923-1 and IEC 62923-2. 7 Interface If the indicator system provides an interface facility, it shall meet the requirements prescribed in IEC 61162-1, IEC 61162-2 or IEC 61162-450.