Breakaway rope
A tear-off rope (also known as a tear- off cord ) actuates the brake of a trailer if it should become detached from the towing vehicle while driving . It is a legal requirement in Germany for trailers with overrun brakes with a total mass of 750 to 3500 kg.
technology
The tear-off rope is put around the neck of the towing vehicle's ball head coupling with a loop and snap hook . If the trailer unexpectedly detaches from the towing vehicle while driving, the handbrake lever is actuated by the pulling action of the breakaway cable and the parking brake is applied. The parking brake must then automatically bring the trailer to a stop "even on an uphill gradient of 18 percent and on a downhill gradient of 18 percent". This prevents the trailer from rolling on without braking after it is unexpectedly released, as cannot be absolutely ruled out in the event of a gross malfunction or incorrect operation of the coupling. While older ball head couplings that have been tested in accordance with EC 94/20 directive often do not have any additional holes or eyelets to accommodate the breakaway cable, such a safety device has been prescribed since March 17, 2010 according to the new ECE 55 R standard . The purpose of guiding the rope through such an eyelet is to prevent the loop from slipping over the ball head coupling. If the hook cannot be passed through the eyelet, z. B. bring a suitably sized shackle remedy. Retrofitting is not required in Germany, but is mandatory in the Netherlands and Switzerland.
According to various publications in Germany, the tear-off rope may only be attached directly to the eyelet without a loop around the neck of the coupling if the hook on the eyelet is a so-called "fire brigade hook" 70 mm according to DIN 5299, since other hooks do not form loops the rope cannot transmit sufficient force.
Special regulations
In the Netherlands, special regulations must be observed with regard to the fastening of the breakaway cable. The so-called "Losbreekkabel" in the Netherlands must not only be looped around the coupling head, but must also be attached to the towing vehicle's coupling using an eyelet (colloquially known as "Holland eyelet") in accordance with Article 5.18.34-2 of the Road Traffic Act . ) or hooks (colloquially "Holland hook") must also be attached. According to the Dutch automobile club ANWB, direct hooking is legally permissible, but not recommended if a hook according to DIN 5299 is not used. Furthermore, for unbraked trailers weighing up to 750 kg, a special tear-away precaution using a steel cable (safety cable) or chain is required. Violations can be punished with a fine of up to 230 euros; this applies to all trailer combinations operating in the Netherlands.
In Switzerland , a similar regulation applies to braked trailers as in the Netherlands. Throwing the breakaway cable over the ball head coupling alone is not permitted; there must be an additional safeguard against the rope slipping over the coupling head. If it is not a "rigid" trailer coupling, the breakaway cable must be secured to the vehicle chassis. These regulations apply to all trailer combinations operating in Switzerland.
literature
- Bert Breuer, Karlheinz H. Bill (ed.): Brake manual. Basics, components, systems, driving dynamics. Vieweg-Verlag, Wiesbaden 2003, ISBN 3-528-03952-3 .
Web links
Individual evidence
- ↑ Breuer, p. 200.
- ↑ Function of the breakaway cable (7)
- ↑ See § 41 StVZO paragraph 9 sentence 4.
- ↑ Breuer, p. 200.
- ↑ Directive 94/20 / EC in the consolidated version of January 1, 2007
- ↑ ECE 55R (PDF)
- ↑ Article 5.18.34-2
- ↑ a b c adac.de Netherlands and Switzerland: Requirement of a safety rope for trailers . Retrieved August 13, 2017.
- ↑ anwb.nl
- ↑ Road Traffic Office of the Canton of Graubünden
