Sounding the alarm without wasting any time
Reliable control solution for alarm systems used on ships
“The Eaton easyE4 is a mature, certified system that we can tailor to our customers' exact needs.”
Background
The engine room of a ship is noisy, and the crew members are busy operating the equipment and can't keep their eyes on control monitors all the time. In order to quickly notify the crew of impending dangers, so-called light signal columns are installed in a ship's service areas: Via acoustic and visual signals, they ensure that the crew is immediately alerted of an emergency, at any time and wherever they work. The light signal columns use specific alarm tones with a volume of up to 120 dB(A) as well as explicit illuminated symbols defined by the International Maritime Organization (IMO), among others, to indicate the type of alarm. The options range from a harmless call from the bridge to a fire alarm.
Challenge
Customized systems that need to be available quickly
“Depending on the ship class and the application, each system requires specific alarms and symbols. For example, some ships require six alarms, while others need indicators for ten alarms,” explains Kim-Ole Glüsing, Project & Development Engineer at sm electrics.
One of the company's strengths is flexibility in responding to orders and its ability to implement special customer requirements quickly.
This also applies to light signal columns, as Mr. Glüsing emphasizes: “For our customers, this means that they don't need to worry about long lead times – after one week at the latest, we will deliver the customized light signal columns that they ordered from us.”
This is particularly important if a ship is undergoing maintenance work because the time spent in dry dock is strictly limited and any delay due to unavailable spare parts is extremely costly.
Solution
Control relays are a robust, cost-effective solution
In order to achieve such short project lead times, sm electrics’ light signal columns are based on a modular design. Depending on the requirements of the customer or the type of ship, different alarm indicators (symbols) can be integrated. The columns, which are installed at various locations in a ship's service areas, are addressed via a central control unit. For this purpose, sm electrics uses control relays from Eaton. “These control relays are much more robust than panel PCs, for example, and thus offer the reliability required for an alarm system,” says Mr. Glüsing. “Additionally, we are able to offer good value for money because our application makes use of the control relays’ full potential.” However, the easy700 control relays that the company has been using to date are increasingly reaching their limits in terms of the number of available inputs and outputs, according to Kim-Ole Glüsing: “We are increasingly implementing systems that require up to 20 inputs and 30 outputs.”
Thanks to its modular design, the easyE4 can be adapted quickly
With the easyE4, the latest generation of Eaton’s ‘easy’ control relays, Glüsing no longer has to worry about any restrictions regarding the number of connections: The easyE4 is designed to be a flexible solution for applications of varying complexity. For example, the eight integrated inputs and four outputs of the basic device can be expanded by up to eleven modules that can be quickly connected via a plug connector. Therefore, in total, up to 188 inputs/outputs are available. “As such, the Eaton easyE4 offers considerably more inputs and outputs than the previous generation,” notes Mr. Glüsing. Thanks to a powerful processor in combination with an interrupt function, the easyE4 also enables fast response times. Incoming alarms are thus processed in the shortest possible time. “The control relay not only collects the alarms, but also sorts them according to predefined priorities,” explains Mr. Glüsing. If several alarms are received simultaneously, the light signal columns will only emit the acoustic signal for the most important and urgent alarm; all other triggered alarms will be indicated by means of the corresponding symbols, which will then light up. Mr. Glüsing explains: “The columns are connected to the control unit via loop-in/loop-out, and the alarms are transmitted as a 230 Volt signal.”
The easyE4 is programmed using the intuitive easySoft7 software. Users can choose between four programming languages: The circuit diagram can be created using function blocks, ladder diagrams, Eaton's own ‘easy’ programming language or by means of structured text (ST). For Mr. Glüsing, the option of using other programming languages with Eaton’s easyE4 in the future is a major advantage in terms of flexibility: “It's always better to have several options with the same proven device than to have to look for a new controller just because of the programming language.”
To safeguard the reliability of the system, sm electrics has also used the easyE4 to implement a number of control functions. But the technical aspects were not the only reason why sm electrics opted for the easyE4 – the control relay also offers all the necessary certifications and approvals for global use. “For our applications in the maritime sector, the DNV GL certification is particularly important,” says Mr. Glüsing. In addition, the rapid availability of Eaton’s easyE4 is also an important factor that enables sm electrics to offer short delivery times.
Result
Where flexibility meets reliability
As Mr. Glüsing emphasizes, “We want to be able to offer our customers flexible, tailor-made solutions with quick turnaround times – with the easyE4, it’s not only the technical features such as the modular design of the control system that make this possible, but also the fast supply chain and the certainty that the devices and any necessary spare parts will be available in the long run.” In addition, sm electrics has also acquired a lot of experience when it comes to using Eaton's control relays in critical alarm systems.
