Operation and Maintenance of AIS Equipment Assessment Practice Questions

Full Text Coverage - Valuation Practice Cross Reference Edition

I. Brief description of contents

(i) Assessment missions:Proper operation and maintenance of AIS equipment.

(ii) Assessment of implementation:

1. Assessment modalities:Use the AIS real machine or simulator for evaluation.
2. Description of the mission (scenario):Operation and maintenance of AIS.
3. Assessment procedures:(1) Basic operation of AIS: self-testing, viewing static and dynamic data and interpreting them; (2) AIS input/output interface settings; (3) AIS connection with other devices.
4. Assessment of requirements:(1) Basic operation of AIS; (2) AIS input/output interface setting; (3) AIS input signal viewing: external GNSS receiver signal and compass signal; output signal to radar, ECDIS or VDR and other devices.
5. Cluster approach:Complete the operation individually. 6. Time for assessment:No more than 10min.

(iii) Elements of assessment and assessment criteria

1. Element of assessment No. 1: Basic AIS operation
Elements: Normal power-up and self-test; view static/dynamic data and interpret.
Criteria: Proper switching on and off and self-testing; static data viewing and setup; dynamic data viewing and setup.

2. Element 2 of the assessment: AIS signaling test
Elements: CPA Alarm test (comparing radar targets); simulated faults to observe alarm consistency.
Criteria: Can perform CPA alarm test; Judgement to disconnect GNSS/rodeo signal; Judgement to disconnect radar output signal.

3. Element of assessment No. 3: AIS connectivity to other equipment
Elements: input signal; output signal.
Criteria: Detection of signals using a multimeter or software; ability to access GNSS/rodeo signals; ability to access signals to equipment such as radar/VDR.

II. Methods of operation

Note: The first evaluation element is presented here as an example.

◎ (i) AIS Basic Operations (Key Elements)

1. Equipment switching on and off:Press the “POWER” key to switch the device on and off.

2. Equipment self-testing:

(1) Monitor unit test:
Press “MENU” to open the main menu; ② Select “DIAGNOSTICS” and press “ENT”; ③ Select “MONITOR TEST” and press “ENT”. Select "DIAGNOSTICS" and press "ENT"; ③ Select "MONITOR TEST" and press "ENT".
a. Display the program number; b. Highlight “PUSH KEY”, press the keys and arrows on the Cursor Pad one by one to make sure the name appears next to “KEY”; c. Check the ROM, RAM, and I/O ports (special test connector is required, otherwise “-” will appear). c. Check the ROM, RAM and I/O ports (special test connector is required, otherwise “-” will appear). The ROM and RAM check result shows “OK” (normal) or “NG” (abnormal); d. Check if the contrast is changed automatically; e. Check the LCD (all LCD segments are turned on for 2s and then off for 3s, the screen turns black and then white again); f. Re-execute the test; g. Exit: Press "MENU" three times consecutively.

(2) Radar transponder testing:
Consists of a memory test and an internal GPS receiver test:
①Memory test: MENU → DIAGNOSTICS → TRANSPONDER TEST → MEMORY TEST. “OK” or “NG” is displayed as the result.
② Internal GPS receiver test: MENU → DIAGNOSTICS → TRANSPONDER TEST → GPS TEST. When “NG” is displayed, it is accompanied by the following reasons: DATA BACKUP ERR, GPS COMMUNICATION ERROR, The display of "NG" is accompanied by the following causes: DATA BACKUP ERR, GPS COMMUNICATION ERROR, PARAMETER BACKUP ERR, ROM ERROR, RAM ERROR, and ANTENNA ERROR.

3. Viewing and setting of the ship's static and dynamic data:

(1) Static data view: Press “DISP” twice to open “OWN STATIC DATA” item, use Cursor Pad “▽” or “▲” to advance or return. Use Cursor Pad "▽" or "▲" to advance or return. The data is shown in Table 3-3-1.

Table 3-3-1 static data

abridge	Full name in English	Chinese Meaning	clarification
MMSI	Maritime Mobile Service Identity	Maritime mobility	9-digit unique identification of the ship, used globally (example: 412345678)
CALL SIGN	Call Sign	cry out in distress	Internationally assigned alphanumeric code (example: BOWA3)
SHIP NAME	Ship Name	name of ship	Ship's registered name (e.g. OCEAN STAR)
TYPE OF SHIP	Type of Ship	Vessel type	Numeric code (e.g. 70 = cargo ship, 35 = fishing vessel, 52 = passenger ship)
DIM A/B/C/D	Dimension	Ship Size	A: Bow to antenna position; B: antenna to stern; C: port side to antenna; D: antenna to starboard side (unit: m)
POSN ANT	Position of Antenna	Locating the antenna position	L:Longitudinal (bow to antenna);W:Transverse (left/right port offset)

DRAUGHT	Draught	Draught of the ship	Current draft value (unit: m, example: 12.5)
DESTINATION	Destination	destination (location)	Destination port to be reached by the ship on the current voyage
ETA	Estimated Time of Arrival	Estimated time of arrival	Format: DDHHMM (Day-Hour-Minute, example: 251830= 25th 18:30)
DEST	Destination	destination port	Port UN/LOCODE code (e.g. CNNGB = China Shanghai Port)

(2) Dynamic data view: Press “DISP” key for 3s to open the ship's dynamic data. The data is shown in table 3-3-2.

Table 3-3-2 dynamic data

abridge	Full name in English	Chinese Meaning	clarification
UTC	Coordinated Universal Time	Coordinated Universal Time (UTC)	Satellite synchronized time (e.g. 120530 = 05:30 on the 12th)
LAT/LON	Latitude/Longitude	Latitude/longitude	GPS location data (example: 31°23.45′N/121°56.78’E)
COG	Course over Ground	course towards the earth	Actual direction of ship's motion (0°~359°, based on true north)
SOG	Speed over Ground	Speed to ground	Actual sailing speed (unit: kn, example: 12.5 kn)
HDG	Heading	bow direction	Bow pointing direction (difference with COG reflects wind flow pressure effects)
ROT	Rate of Turn	gear shift ratio	Right turn is positive/left turn is negative (unit: °/min, example: +12)

(3) Data setup and modification (MMSI, IMO, ship name, call sign):
①MENU → ②INITIAL SETTINGS → ③Enter password → ④SET MMSI → ⑤Enter 9-digit MMSI → ⑥IMO No. (Note: 7-digit No. needs to be preceded by “00”, and 9 0s are input for no No.) → ⑦NAME (ship's name, not more than 20 characters) → ⑧C.SIN (call sign, not more than 7 characters) → ⑨ENT to confirm, press MENU to save. SIN (call sign, not more than 7 characters) → ⑨ENT to confirm, press MENU to save.

(4) GPS antenna position setting (SET ANTENNA POS):
①Enter initial setting → ②SET INT ANT POS (built-in) → ③Press ENT to input A (Bow distance, 0~511m) → ④Enter B (Stern distance, 0~511m), C (Port distance, 0~63m), D (Starboard distance, 0~63m) → ⑥Similarly set the parameter of SET EXT ANT POS (external) → ⑧MENU to save.

(5) Vessel type setting: Initial setting → Select vessel type setting → Confirm the number and MENU to save.

4. AIS information view of other ships:

①Static information: Short press “TARGET” twice to enter TARGET LIST → select target ship and press ENTER → MENU → STATIC DATA.

See Table 3-3-3 for other ship static data.

Table 3-3-3 His ship's static data

abridge	Full name in English	Chinese Meaning	clarification
MMSI	Maritime Mobile Service Identity	Maritime Mobile Business Identification	9-digit unique identification (example: 412345678)
CALL	Call Sign	cry out in distress	Internationally assigned code (example: BOWA3)
NAME	Ship Name	name of ship	Registered name (example: BLUE OCEAN)
TYPE	Type of Ship	Vessel type	Numerical code (70 = cargo ship, 35 = fishing vessel, etc.)
DIM A/B/C/D	Dimension	Ship Size	A: bow to antenna; B: antenna to stern; C/D: port and starboard to antenna (m)
DRAUGHT	Draught	draft	Current draft value (example: 10.5m)
DEST	Destination	destination port	UN/LOCODE code (e.g. CNNGB=Shanghai Harbor, China)
ETA	Estimated Time of Arrival	Estimated time of arrival	Format: DDHHMM (Example: 251830 = 25th 18:30)

②Dynamic information: Short press “TARGET” twice to enter TARGET LIST → select target and press ENTER → MENU → DYNAMIC DATA. or short press “TARGET” once to lock the target and then press “DATA” to pop up. or briefly press "TARGET" once to lock the target and then press "DATA" key to pop up.

Other ship dynamic data are shown in Table 3-3-4.

Table 3-3-4 Other ship dynamics data

abridge	Full name in English	Chinese Meaning	clarification
UTC	Coordinated Universal Time	Coordinated Universal Time (UTC)	Data update time (Example: 120530=12th 05:30)
LAT/LON	Latitude/Longitude	Latitude/longitude	Position of target vessel (example: 31°23.45′N/121° 56.78’E)
COG	Course over Ground	course towards the earth	Actual direction of motion (0°~359°)
SOG	Speed over Ground	Speed to ground	Current speed (kn, example: 14.5 kn)
HDG	Heading	bow direction	Bow pointing (difference with COG reflects wind flow pressure)
ROT	Rate of Turn	gear shift ratio	Right turn +/Left turn - (unit: °/min, example: +8)
CPA/TCPA	Closest Point of Approach/Time to CPA	Nearest point/time of encounter	Critical parameters for collision avoidance (e.g., 0.5 n mile/12 min)

◎ (ii) AIS signaling test

1. CPA alarm function test:

(1) MENU → USER SETTINGS; (2) Select “CPA/TCPA ALARM” to set the range and time.
(3) Set the same CPA LIMIT and TCPA time on the radar display screen.
(4) Select a moving target in the AIS target list and record its MMSI, COG, and SOG. manually capture the target on the radar.
(5) When the vessel enters the CPA range, observe if the AIS and radar trigger an alarm simultaneously.

2. Simulated fault testing:

Manually disconnect the GNSS receiver or rosette signal and check if the screen alarm corresponds to the actual fault.
Manually disconnect the AIS output to the radar and check for alarm messages on the radar.

:: (iii) AIS connectivity to other equipment (key element)

1. Input signals:

(1) MENU → INIT SETTINGS → SET I/O PORT → SET COM PORT.
(2)Select the port (COM5/6 is the sensor interface). (3)MODE Select “SENSOR”.
(4) Rate setting: IEC 61162-1 (4800 bit/s) or IEC 61162-2 (38.4 kbit/s). Press ENT to confirm and MENU to save.
(5)Detection:Read the input NEMA signal using the DC 5V block of a multimeter, and observe that 0.5~1.5V Oscillation for normal. Connect the device to the TD terminal.

2. Output signals:

(1) Set the path to the same input signal and select the port (COM1/2/3).
(2) MODE Select “LONG RANGE” (Inmarsat C) or “EXT DISPLAY” (Radar/ECDIS/PPU).
(3) Rate setting: select 4800 or 38.4 kbit/s according to the radar/VDR requirement.MENU save.
(4)Detection:multimeter reading 0.5~1.5V Oscillation is normal. Signal is connected to RD terminal.

AIS Data Classification and Update Frequency Quick Reference Manual (Essential for Evaluation)

(1) Static Data - sent every 6min or on request

Project name	Specific content description
MMSI / IMO No.	Maritime Mobile Identifier (9 digits) / IMO number (7 digits).
Name / Call Sign	Ship name (up to 20 characters) / Call sign (up to 7 characters).
Antenna Pos	A/B/C/D dimensions for precise positioning of the vessel's outline position on the electronic chart.
Type of Ship	Ship type code to distinguish between cargo ships, tankers, passenger ships or special ships.

(2) Dynamic Data - Update Frequency: 2s ~ 3min (depending on speed and heading)

Project name	Specific content description
Position (L/L)	Latitude and longitude coordinates, provided by the GNSS receiver.
COG / SOG	Course Over Ground and Speed Over Ground.
HDG / ROT	Heading and Rate of Turn.
Nav Status	Navigational status: e.g. underway, anchored, out of control, limited to draft, etc.

AIS Equipment Use, Operation and Maintenance Hands-on Score Sheet

Candidate's name: ________________
Evaluation time: 10 minutes
Total points: 100

Elements of assessment	Operational Standards and Key Points	value of a score
basic operation (30 points)	Perform the power-on self-test (MONITOR TEST / TRANSPONDER TEST) correctly.	10
	View and accurately interpret the ship's static and dynamic data (MMSI, L/L, COG, etc.)	10
	Correctly set/modify vessel information (vessel name, call sign, antenna size A/B/C/D)	10
signal testing (30 points)	Configure CPA/TCPA alarm thresholds and verify synchronized comparisons on the radar	15
signal testing (30 points)	Analog Sensor (GNSS/Rodometer) Loss, Identify Alarm Message Consistency	15
Interfaces and Connections (40 points - critical)	Set the I/O port mode (SENSOR / EXT DISPLAY) and rate (4800/38.4k).	20
Interfaces and Connections (40 points - critical)	Measure the NMEA signal level with a multimeter (observe 0.5~1.5V swing).	20

Note: Time-outs, incorrect operation of key elements, or incorrect selection of multimeter settings will directly result in failure of this assessment.