SAFEMASTER STS offers protection options for plants, and combines the advantages of safety switches, guard locks, key transfer and command functions all in a single system

In depots and maintenance plants for railway technology, danger zones on trains must be protected with isolating protective devices. These are large-area installations over several levels and maintenance personnel are often exposed to hazards during maintenance work including:

  • Electric shock.
  • Danger of falling.
  • Danger of being locked in.
  • Fire hazard.

Safeguarding these extensive depots with electrical components requires a large amount of wiring, which can be prone to faults. There are currently no specific standards for railway maintenance depots. However, working platforms and machines are generally planned in accordance with the requirements of the Machinery Directive 2006/42/EC. The safety devices must generally achieve a Performance Level d or PL e in accordance with EN ISO 13849-1. In maintenance depots the high voltage must be switched off via manual operating points or control systems.

In addition it must be ensured that there is no danger of falling (in pits, lifting platforms and roof-mounted work platforms), operating sequences must be adhered to particularly when accessing the train roof. It is often necessary for operating personnel to put on safety harnesses, use extend folding steps and ground / earth overhead lines using telescopic rods. Due to the size of these installations and the different access levels, it must be ensured that when the train is moved, the maintenance personnel have all left the danger areas and that all maintenance and safety doors are closed. In addition, any locked in operators must have a means to escape.

With the SAFEMASTER STS safety switch and key transfer system, predefined processes can be enforced. This is achieved by the key transfer function. The ability to protect access and safety doors mechanically and without wiring saves installation cost and increases the availability and ergonomics of the plant, so improving productivity.

SAFEMASTER STS combines the advantages of safety switches, guard locks, key transfer and command functions in a single system. The new fibre reinforced polymer (FRP) variant impresses with its sleek functional design and its ability to be combined with the established stainless steel system. You can select the FRP variants for the control panel and use the robust stainless steel versions in rough environmental conditions.

SAFEMASTER STS is tested and approved according to statutory requirements, and as a stand alone or monitored system is suitable for use in safety applications up to Cat. 4 / PL e in accordance with EN ISO 13849-1.

Essex-based firm, DOLD Industries, is proud to have an almost 100-year track record in the production of quality products to the manufacturing industry. Founded in 1928 by Emil Dold, the company’s origins are rooted in the best of Black Forest traditions. While the main manufacturing plant remains in Germany, the company’s base in Essex distributes the full range of safety and automation solutions for the UK.

Guaranteed electrical safety and reliable availability represent prerequisites for smooth railroad operations. This applies to locomotives and wagons just as much as to signalling systems, signal boxes, tunnels and bridge constructions. This means that system solutions are needed that ensure the continuous monitoring of electrical equipment and railroad facilities. Besides this, early warnings must enable troubleshooting before critical conditions arise.

Other products in DOLD’s repertoire include level monitoring for water tank monitoring and relays for trackside switching.

Systems and equipment are becoming more and more complex, due to growing automation, rationalisation, and the increasing use of control electronics in machines. Required maintenance work is increasing, making it more difficult for humans to modify such systems. Preventative maintenance which helps avoid malfunctions or reliably correct them in a short time helps to save costs. Using measurement and monitoring relays is becoming more and more economical, as lost production time is difficult to make up.

The situation is all too familiar – complex production systems, high demands for quality, delivery time, and delivery reliability, with permanent cost pressure. Today more than ever, these
kinds of pressures require comprehensive operational readiness to maintain and even improve international competitiveness. In practice, however, comprehensive operational readiness is often difficult to achieve; ageing, moisture, contamination, mechanical damage, and other factors can lead to creeping insulation failures. Such undiscovered issues can lead to cost-intensive system and operational standstills, repair costs, and typically high follow-up costs due to production shutdowns. In the worst case scenario, insulation failures can even be a frequent cause of fires and personal injuries.

DOLD has a range of solutions including insulation monitors and fault locator units, with the multifunction measuring relay for Modbus UG 9400 simultaneously monitoring up to nine different measured variables such as voltage, voltage asymmetry, current, cos phi, active, apparent and reactive power as well as frequency and phase sequence.

Reliable switching and controlling is a mainstay of the product line, with semiconductor contactors which have proven themselves in industrial applications in any situation where high switching frequencies or high switching cycles are required. With their long service lives and wear-free switching, they handle switching and controlling tasks in specific applications in a highly economical manner.

Safety technology is becoming more and more important in machine and equipment construction. Safety modules or even safety controllers are being used everywhere.

A pioneer in the production of Switchgear, E. Dold & Söhne GmbH & Co. KG is one of the leading European manufacturers and is certified to ISO 9001. DOLD develops, manufactures and distributes high-quality components and complete solutions for safe automation, electrical safety and smart drive technology worldwide. The product range includes safety relay modules, safety relays with forcibly guided contacts, electronic enclosures as well as safety switches, safety guard locks and key transfer systems.

Tel: 01245 324432
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