Switchgear and sensors for shipbuilding and port technology

The demands made on the switches and sensors of today are steadily increasingly due to the growing complexity of their application areas. In shipbuilding and port technology, the ambient conditions are particularly challenging, and normal switching devices soon meet their limits. As a reliable partner with close contact to our customers, we were able to recognise and tackle this problem very early on, developing products which really come into their own in such rough environments. Our innovative switches and sensors are ideally suited to extreme applications and have to prove their reliability in field tests which are sometimes extraordinary. With our "Product assessment for maritime applications", we also help our customers to find the right switching devices for their individual needs.

Tests under laboratory conditions

Salt-mist tests and degrees of protection

There are several industrial standards that can be used to test the corrosion resistance of electrical equipment. They start with simple salt spray tests according to DIN EN ISO 9227 and rise to cyclic salt-mist tests according to IEC/EN 60068-2-52 that can run for many weeks. In all of these standards there are uniform defined laboratory environments to obtain reproducible and therefore always comparable results. Unfortunately, there is rarely a direct connection with actual practice. For this reason, some classification authorities, such as DNV-GL, work with their own standards in compliance with the relevant business field.

Degrees of protection are defined in e.g. IEC/EN 60529. Definitions refer, amongst other things, to the protection of live wires against contact or the penetration of water. Practically applicable degrees of protection for the maritime area start at IP 65, although all degrees of protection according to the IEC/EN 60529 standard are tested on new devices only. Here is an example of the degree of protection for IP 66. At a distance of 2.5 to 3.0 m, devices are treated with spray water that hits them at 100 l per minute from different directions. The water jet diameter is 12.5 mm and the test duration is at least 3 minutes. Many steute Extreme products have a degree of protection between IP 65 and IP 69 with an additional salt-mist test. Despite the limitations of industrial standard tests for actual practice, high degrees of protection and good salt-mist test results are still decision criteria when selecting devices.

Field trials under real maritime conditions on the North Sea island of Helgoland

Testing under real-life conditions

Results from salt-mist tests are rarely suitable for comparing the long-term behaviour of different coating or coating systems because the corrosion stress in such laboratory tests differs significantly from actual practice. Degrees of protection are always tested according to the standard on new devices only. This is why steute has implemented its own long-term tests under real-life and demanding conditions in addition to the laboratory and standard tests according to industrial specifications. Here the corrosion behaviour, the function and the degree of protection are all evaluated in practice.

In the first test phase from September 2017 to September 2018, i.e. a total of 8400 hours, various steute Extreme switches were exposed to out-door maritime conditions. In the test set-up, a sample device selection was placed 1 metre above the surface of the water in the “splash zone”. At the end of the test phase, the corrosion and function of the devices were evaluated. A new practice-oriented comparative parameter was thus created: “According to the typical climatic conditions at the Helgoland site in the North Sea over the course of one year”.

The results from these outsourced field tests were then transferred to identically constructed devices and included in the product lists of devices recommended for the maritime sector.

Switch rating für indoor and maritime outdoor applications

In order to simplify the choice of a suitable device, our switches and sensors were assessed for two different types of maritime environment:

Suitability for indoor areas (e.g. engine room)
Suitability for outdoor areas (e.g. decks, cranes, ports)

Important assessment criteria included corrosion resistance, protection class and fouling resistance with regard to function.

We then translated the results of this assessment into four categories of suitability (highly recommended, recommended, suitable and conditionally suitable). These categories are further underlined in the product lists with easily recognisable quality seals.