The final report of the technical investigation on the Bozankaya tram from Timișoara confirms the statements of the producer: a human error caused the battery system to overcharge
April 27, 2022, 7:00:00 AM
After the incident which occurred on March 30, 2022, inside the Dâmbovița depot in Timișoara, where there have been smoke emissions from the Bozankaya tram no.5, the independent, internationally accredited auditing company TÜV Thüringen, which has been particularly requested by the Municipality to be assigned for investigating the incident, and organized by Bozankaya, conducted a two-week investigation on the vehicle, specifically on the battery system. The report issued by TÜV Thüringen, based in Germany, supports the preliminary findings announced by the Turkish producer Bozankaya, stating that an individual human error led to the overcharging of the battery system.
In the report that resulted from the investigation, the battery expert inspectors of the German technical audit company conveyed that the smoke arose from a communication interruption caused by an individual wiring error in the relevant battery system.
”The overcharging of the battery cells provoked a chemical reaction by disrupting the cells’ physical structure, eventually causing, at high temperatures, arcing and smoke emissions”, shows the report issued by the TÜV Thüringen experts.
Upon the fulfillment of the investigation of the tram involved in the incident, the inspectors also examined all the other Bozankaya trams from the depot to make sure that no other wiring operations had been conducted improperly.
”All the Bozankaya trams are tremendously safe and, without exception, all critical tests - the technical, safety, and quality - are meticulously conducted during such testing phases, before any Municipality commissions the vehicles, as was the case in this situation. All Bozankaya branded vehicles used both in Europe and Asia provide flawless service for years with high satisfaction rates”, declared the representatives of the Turkish company.
The Bozankaya vehicle involved in the Timișoara incident was still undergoing the required tests before being commissioned to the beneficiary, Timișoara City Hall, the in-situ verification of the trams before the operation being part of the mandatory test protocol imposed by the Turkish producer.
Also, the battery system designed for the trams delivered in Timișoara was manufactured with state-of-art technology, which is why, in 2021, Bozankaya won the ERCI (European Railway Clusters Initiative) award in the "Best Large Enterprise" category. The jury of the most prestigious institution dedicated to European railway system technologies appreciated the alternative solution aiming at the economy at the investment costs in the electrification of the catenary suspension, maintenance, and service of the classic infrastructure.
About TÜV Thüringen
TÜV Thüringen is an internationally accredited German auditing company, specializing in a wide range of services related to vehicles’ safety and quality, like measurement, testing, analysis, identification, calibration, expertise, certification, and consulting. These include both classic tests for the safety evaluation of equipment or vehicles and testing of products or materials in laboratories.
Founded nearly three decades ago in Germany, with a rapid expansion in Turkey, Bozankaya has a strong track record as an innovator in developing and manufacturing environmentally friendly, energy-saving, low-noise, and low-cost vehicles for the urban public transport. Bozankaya owns the intellectual property rights for the vehicles and technology produced at its research centers in Ankara and at its vast production facilities, measuring 100.000 sqm. Maintaining a strong focus on R&D, the company has spent more than 25 million euros on 30 R&D projects within the past five years. In June 2018, Bozankaya became the first Turkish company to export metro trains, with the first shipments going to the Green Line Project in Bangkok.