Spring-applied actuators brake the vehicle after an energy failure thus providing an indispensable safety instrument. After braking, however, there is a slight technical problem: the vehicle cannot be moved unless there is hydraulic pressure in the service release circuit. HANNING & KAHL has designed auxiliary release devices for this particular application. These devices can build up pressure in the actuator's second hydraulic circuit independently of the service release circuit. The brake can be released with this pressure allowing the ve hicle to be moved again. An auxiliary re - lease de vi ce can be deployed to release all the brakes on a tram or just the brakes of a particular bogie dep end ing on the vehicle design.
|type||HP||HZY NL||HZY NL/HP|
|equipment||stationary hand pump||electrically propelled small hydraulic power unit||electrically propelled hydraulic power unit in connection with hand pump|
|mech. design||frame type||compact||compact|
|mounting location||car body (driver’s cab)||bogie||car body|
|application||manual release per car or per bogie||electrical release per bogie||manual or electronic release per car|
|functions||manual op. release, manual op. braking, electronic. op. braking||electric. op. release, electric. op. braking||manual op. release, electric. op. release, manual op. braking, electric. op. braking|