It is something that one normally never notices, but which is always there in a crisis: emergency lighting. In the event of an accident, it helps first responders to reach the scene of the accident, and to find their way out again if there is a fire. To keep the lights on even in the event of a power failure, the distributor boxes in the railway tunnel have to withstand pressure waves from passing trains, along with temperature fluctuations, dust and dirt. HERMOS Systems GmbH has relied on Rittal enclosures for over 25 years. They are robust, certified and there for the long run, allowing people to get out of the tunnel safely and at any time.
Overview
- Project
- Hermos GmbH/Deutsche Bahn AG
- Location
- several locations, Germany,
- Branch
- Rail
- Challenge
High-speed railway tunnels are subject to tough operating conditions; the technology employed must meet high safety requirements and possess the certifications that the railway company requires
- Solution
AX plastic enclosures are tested for suction and pressure resistance, are halogen-free and meet the UL 94 V-0 and UL F1 outdoor rating standards, possess UL approval for industrial enclosures. They must also have a protection category up to IP 66/NEMA 4X for the encapsulated space and Class II protective insulation.
We have been using the plastic enclosures from Rittal since 1999 and have had nothing but good experiences with them.”
In such uninviting places as tunnels for high-speed trains, technical equipment is subjected to major burdens. It has to withstand pressure waves from passing trains, temperature fluctuations, swirling dust and the moisture that penetrates every crack. In the event of a railway accident or a fire in the tunnel, features such as the emergency lighting system and its power supply must not be allowed to fail. After all, the safety of the rail passengers and staff depends on them functioning flawlessly.
The railway is aware of its great level of responsibility and has set high standards for the operation of its technical facilities. Numerous regulations and specifications define the technical standards and certifications needed. They also specify the small number of authorised operators and suppliers. If any changes are made to the feature or product, a new certification will be required immediately, and that includes a one-year practical test.
Rittal AX plastic enclosures: robustly built and easy to assemble
HERMOS Systems GmbH has overcome all these hurdles and is responsible for much of the safety lighting in the tunnels of Deutsche Bahn’s German rail network. Since 1999, HERMOS has been using Rittal enclosures to house the power supplies for its lights. More recently it has been employing plastic enclosures of the AX series. They are available for delivery long-term and are extensively certified. “We use them because they all have certifications,” says Veit Demel, Managing Director of HERMOS Systems GmbH. Some of these certifications are indispensable: Proof of resistance to suction and pressure is required to withstand the pressure waves of the high-speed trains that rush past. That’s why Rittal subjected the plastic enclosures to an elaborate suction and compression strength test in a wind tunnel. Since the enclosures hang in the open air near the entrances, they are exposed, unprotected, to the weather and temperatures ranging from −20 to +40 degrees Celsius. With a UL F1 outdoor rating, Rittal can show that the AX enclosures can withstand UV radiation, moisture and underwater conditions without incurring any damage. In the encapsulated area, the enclosures even comply with protection category IP 66/NEMA 4 X. This means that they are protected against swirling dust and water, corrosion, ice formation and oil leaks. And if a fire does break out in the tunnel, no corrosive or toxic gases are released, as the plastic housings are made of halogen-free material and fulfil the UL 94 V-0 fire protection standard. Of course, they also have the UL approval for industrial enclosures. Furthermore, all the conductive components have reinforced Class II protective insulation.
Rittal and HERMOS have consequently taken thorough precautions to ensure that the emergency lighting in the tunnel never goes out.