The first fisheries protection vessel, the Lilian Ngoyi, undertook her maiden voyage at the end of November 2004. Constructed in Cape Town using more than 50% locally sourced construction material and 200 000 hours of South African labour, it was no surprise that Spectrum Communications, the local telemetry systems integrator chosen to implement the vessel's management system, elected to install a Proudly South African supervisory control and data acquisition (scada) - Adroit - as part of the sophisticated management system for this state-of-the-art vessel.
"This is a local product that sets new international standards for environmental safety, protection and performance," said Marthinus van Schalkwyk, minister of environmental affairs and tourism, speaking at the official christening of the Lilian Ngoyi.
Built specifically for the Department of Environmental Affairs and Tourism by Farocean Marine, the almost $10 million Lilian Ngoyi is the largest vessel to be built in Cape Town in the last 25 years. It is the first of three state-of-the-art in-shore environmental protection vessels and will be joined by a $19 million offshore vessel during the course of 2005.
Biggest in their class
Larger and more powerful than other international protection vessels, these valuable new additions to marine and coastal management in South Africa are designed for South African conditions, some of the most challenging in the world. They are 47 metres long and 8 metres wide and can reach a top speed of about 25 knots (about 40 km per hour) with a cruising speed of 17 knots (about 30 km per hour), which is roughly twice the speed necessary to catch most poachers. The normal speed of a vessel is between 12 and 13 knots.
Ship management system
The management system designed for the Lilian Ngoyi by Spectrum Communications is a culmination of many interacting parts and monitors various transducers. Connected to two identical Spectrum Communications tele-FLEX telemetry devices and a supervisory controller, two Adroit scada packages form the user interface on separate, networked computers. Tele-FLEX is an advanced telemetry system from Spectrum Communications, designed to provide flexible communication solutions for a variety of applications.
This sophisticated system retrieves data from three different elements on the vessel and represents it in a visual format that the end-user can easily navigate. The three points of incoming data are: a serial interface to the MTU engine monitoring unit, a serial interface to the vessel's power system, and inputs directly connected to the Spectrum Communications tele-FLEX telemetry unit. The tele-FLEX telemetry collects and processes the data from the three inputs, processes it and forwards it to the Adroit scada.
Visualisation
With the Adroit software package, the management package is a visual tool that represents realtime data of events on the system and logs the data to provide reports in Excel showing historical data in a graphic trend and notifies users of alarms on remote displays throughout the vessel.
The first scada screen provides an overview of the main engine room. Buttons above and below this mimic direct the user to different screens such as bilge levels, tank levels, housekeeping, alarms, power system, MTU reports, engineers log, doors and hatches, hire monitor, airconditioning, sewage system, bow thrusters, steering gear, fresh water maker, and battery pack. The user can also click on various images on the overview screen to receive more information on that particular aspect of the vessel. The port and starboard engines' status and values are monitored by the system and are displayed in text and graphical format. By clicking on any of the sensor display values in the system, the trend screen will open displaying the selected item's historical trend. The span of the trend is two days, but can be changed if required.
The bilge level sensor points are displayed via a top view of the Lilian Ngoyi. When the sensors make contact with the water, the normal state of the software will change to a high level warning and an audible beep will sound. The information for this condition is also available on the alarm page like all alarm conditions in the system.
When a new item is logged into the alarm page, then a beeper will sound until the alarm is acknowledged by operating personnel. The colour of the text on the alarm will change once it has been acknowledged. When the alarm is rectified, the item will remove itself from the alarm list.
All level sensors are also displayed in a top-level view of the vessel with display balloons showing the information received from the sensor. Actual levels are displayed in percentages except for the disbursement tank, engine lube oil tank and gearbox lube oil tank, which only use the sensor to detect a high or low level. If there is a problem with the level sensor or the connection to the sensor an alarm condition will be displayed in a balloon to warn the operator.
Fire monitoring
A fire-monitoring screen has been created. As a standard throughout the software package all conditions displayed in green symbolise a normal condition and conditions displayed in red symbolise an alarm condition that must be attended to. The conditions for fire dampers, extinguishers, extinguisher pressures, the release box as well as the actual fire alarm are all represented on the screen.
The airconditioning, sewerage, bow thrusters and fresh water mimic screen displays monitored information for these four categories. Buttons containing the condition of each of these components, such as the two airconditioner condensers and two compressors, appears alongside a descriptor. The condition for each item is displayed and only one of these conditions will be visible if the system is in operation. With similar functionality and visuals, monitored information from the CPP, Stern Seal, Stern Tube and Steering share a mimic page.
Monitored battery charges and stabilisers have their information displayed on a separate mimic screen and buttons for the deck crane and davit power pack have also been inserted on this screen for future use. Supply of voltage to the port and starboard, as well as to the generator also has its own monitoring page.
All inputs monitored on the system are logged to hard drive once every minute. A special directory on the system keeps these data log files where this information is stored for one year. Data for longer-term storage is saved onto removable media. Statuses logged from the MTU screen can be printed or saved to an Excel database for e-mail purposes.
The engineer's log is set to save and print a snapshot of selected information every four hours using a predefined template as a container for this data. Each file and printout is time stamped when the data is transferred. On the engineer's log screen, the printer can be disabled without hampering the regular reports being saved to disk.
Housekeeping
The housekeeping screen displays the status of all the units that make up the management system such as communication systems, tag points licensed and used, server mode, computer status, and Spectrum tele-FLEX communication status and so on. The beeper enable/disable buttons allow the operator to arm or disarm the beeper when the alarm sounds. The communications will display 'healthy' if the communications to a certain item are good or 'commsfail' if communication could not be established.
On this page the operator can also select which will be the active telemetry rack and which the standby by clicking on the 'Rack A' or 'Rack B' buttons. The page also contains a button to access various diagnostic functions.
Master/slave operation
The Adroit version 5 scada packages are running on two Pentium 4 computers with 40 Gb hard drives. TF_M telemetry device and a TF_S supervisory device using a Modus RTU protocol.
The two computers running the Adroit scada packages interact with each other to determine which will be master and which the slave. The two telemetry modules report their status to the Adroit each second. If the status of the master telemetry unit cannot be established, the scada will automatically switch the processing of the data to the standby rack, which will then become the master unit. If the previous master unit comes online again it will automatically be set as the slave unit. The status of both the master and slave units can be monitored on the housekeeping screen in the Adroit package.
Telemetry
The telemetry units each consist of 10 RS232 communication ports, 24 12-bit differential analog inputs, 100 digital inputs and four digital outputs. Eight of the RS232 communication ports are connected to RS232 and RS485 converters, which in turn are connected to the various field units. The field units constitute to connections to the MTU monitoring unit, one to the Kaltron MCC panel's PLC, four to the remote displays and one connection to the two scada computers.
Communication to the MTU monitoring equipment uses a proprietary protocol, while the balance of the communications devices uses the Modbus RTU protocol.
Remote displays
There are four remote displays in the vessel, one each in the captain's cabin, the chief engineer's cabin, engineer's cabin and the messenger's room. The remote displays have two lines and display the two most active alarm states. When a new alarm is triggered the alarm group name is sent to the four remote display units followed by an audible beep. The beep will silence after the alarm is acknowledged in the wheelhouse. After the alarm is read on the remote display it can be cleared by pressing the escape button.
The remote displays have a built in Modbus master driver and are set up to read the information from the tele-FLEX at one second intervals. The devices are pre-programmed with a list of alarm groups that are linked to an integer value for each group. The Adroit scada determines the group to which the alarm belongs and sets the predefined value in a register in the tele-FLEX. The remote display will read this value and then display the related alarm group onscreen.
The PLC in the Kaltron panel is set up as a Modbus slave unit. The tele-FLEX polls the required data as determined by a predefined time period and put it in the respective registers for retrieval by the Adroit scada packages.
The scada computer terminals are located in the electronics room of the vessel. Two keyboard/video/mouse (KVM) switches route the user input and video output to the wheelhouse.
Between the computer room and the wheelhouse, three cables link each computer, a KVM switch routing cable (8 wire CAT 5), a touch screen interface cable (5 wire RS-233 CAT 5), and a 220 V supply cable for the touch screen and KVM remote unit. The KVM switch consists of two units, a local unit is fitted above the Adroit scada, and the remote unit is located behind the LCD touch screen in the wheelhouse. The two touch screen panels are located on the starboard side of the wheelhouse. An invisible resistive sheet covers the LCD making mouse-like functionality available through finger contact with the screen.
Special routers were added to the management system to provide communication due to the distance between the computers, printer and monitors. A 100 Mbps switch is located in the electronics room, which connects the master computer, slave and printer. This is an isolated network. A special network card is used to connect the A3 printer directly to the network, making the printer independent of the two computers.
"These new vessels, named after great South African women, will serve as the protectors of our marine resources and our marine environment, against poaching, over-consumption, over-fishing, and environmental hazards like oil spills," said minister Van Schalkwyk. "In addition to their fishery and environmental protection functions, these vessels will also be ready for search and rescue, and are capable of providing first aid in fire fighting and towing operations around our coast."
Lilian Ngoyi was the first woman to be elected to the National Executive of the African National Congress. "Like Lilian Ngoyi, Ruth First, Victoria Mxenge and Sarah Baartman the strength of these vessels is rooted deep in our South African pride," he says.
Speaking about the deterrence value of the new vessels and the 40 new fishery conservation officers being appointed to crew them, the minister added, "This will move South Africa into a whole new era of fishery compliance and, for the first time in many years, will give our department a presence right around South Africa's coast. We plan to have each of the inshore vessels at sea for 225 days per year, and this will be increased over time as our operating budgets increase."
| Tel: | +27 11 658 8100 |
| Email: | [email protected] |
| www: | www.adroit.co.za |
| Articles: | More information and articles about Adroit Technologies |
| Tel: | +27 21 001 5500 |
| Email: | [email protected] |
| www: | www.spectrumcom.co.za |
| Articles: | More information and articles about Spectrum Communications |
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