Krzysztof Dyl, the President of the Rail Transport Authority in Poland, approved the 741.7 class locomotive modernised by CZ LOKO for operation in Poland on 25 September 2015. A difficult three year approval process led to document Nr PL 51 2015 0013, which enables this locomotive to operate as a shunting and main line service vehicle on the 1 435 mm gauge.
The four-axle 741.7 class diesel-electric locomotives are equipped with the MSV elektronika digital control system, the 1 000 kW CAT 3508 C diesel engine, Siemens alternator, and AC/DC electric transmission. The locomotive´s maximum speed is 100 km/h and has an axle load of 18 tonnes. The lower hoods provide the engine driver with greater visibility.
The initial 740, 741, and 742 class locomotives undergo a complex modernisation according to internally designed plans in the CZ LOKO factories. The original main and bogie frames are blasted with abrasives and checked by a defectoscope. New, patented crash-absorbing elements are mounted on new buffer beams. The new diesel motor, traction alternator, driver’s cab and other replaced components make these modernized locomotives comparable to brand-new locomotives.
High reliability and extended maintenance cycles allow for significant cost savings. The vehicles meet the current EU Stage IIIA emission limits. The 741.7 locomotives offer high comfort and safety for engine drivers and shunters. Among the functions of the novel digital control system of which the engine driver can take advantage is automatic speed control (ASC). The multiple control system enables two or more CZ LOKO locomotives to be driven singlehandedly even when powering very heavy trains in demanding conditions. The new rheostatic dynamic brake system significantly reduces brake system maintenance costs. The installed wheel slip protection system guarantees better use of traction effort in unfavourable adhesive conditions.
“The approval process of the 741.7 was challenging for the designers, technologists, technical document creators, and production. To complete the process, the locomotive underwent necessary modifications to fulfil many tests and examinations on Polish tracks and test circuit. The complexity of approving and certifying railway vehicles in Poland is well-known throughout Europe. By achieving certification under updated legislation, CZ LOKO is fully prepared to offer locomotives of additional classes with full certification to Central European railway operators. The 741.7 locomotive is being successfully operated in the Czech Republic, Slovakia, Turkey, and Italy.” Martin Svercl, CZ LOKO’s Export Manager explains.