"When frost was expected in the past, we used glycerine as a defroster to keep the overhead lines free of ice. Our catenary maintenance vehicle, which was equipped with a pantograph including a lubrication device, was deployed for this purpose. The dispatcher in the control center had to decide whether to use the vehicle based on the weather conditions."

"If so, this meant that a streetcar driver had to drive the entire route network again with the catenary maintenance vehicle after the last trip to lubricate the overhead lines with glycerine. The two-hour extra trips naturally met with little enthusiasm from his colleagues ..."

"Lubrication driving was not only a nuisance, it was also very time-consuming and costly. No wonder, because the catenary maintenance vehicle was used every day in freezing temperatures, i.e. 30 to 40 times per winter season."

"It wasn't easy for the control center to assess whether the catenary maintenance vehicle needed to be deployed or not. We agreed that glycerine would be lubricated at temperatures of 1 degree Celsius and lower to be on the safe side. Because once the overhead line is frozen, it's too late ... In hindsight, we have to say that 80 percent of the trips were unnecessary."

"As a customer of Schunk Transit Systems, we benefit from regular contact with their field service. Our contact person had already introduced us to the ice scraper carbon strip some time ago. The scraper is fitted with a copper rail that removes ice from the contact wire. However, we were concerned that this rail could damage the overhead line. That's why I initially only used the Schunk solution on the catenary maintenance vehicle."

"After we had successfully tested the Schunk solution on the catenary maintenance vehicle, the time had come in the winter of 2022/23: We equipped 3 of our 10 streetcars with the special collector strips - 2 pieces per vehicle. The conversion was very straightforward and took less than half an hour per contact strip. To ensure that the equipped vehicles were the first to drive ahead in the morning to clear the overhead line of ice, extra parking spaces were reserved for these tramways."

"Today, we can say: we are delighted with the ice scraper carbon strip! Last winter, we were able to almost completely dispense with expensive glycerine spraying. The de-icing of the contact wire worked reliably and brought us enormous savings. To be precise: 2 weeks of machine use per month, a total of 120 working hours and 80 % glycerine.

Only in one case did the overhead line have to be burned free due to very difficult weather conditions. In very high humidity and very low temperatures, such extreme frost had formed that it could not be removed with either the ice scraper carbon strip or glycerine."

"By using the ice scraper contact strips, we were able to avoid train failures caused by the weather. In the past, failures had occurred in severe frost, as very low temperatures can mean that the glycerine is not always applied evenly. This can still lead to icing in places. We didn't have this problem with the Schunk solution."

"Contrary to our fears, we have not had any negative experiences with wear on the contact wire. The grinding pattern on the contact strips was completely normal. In terms of service life, we assume that the contact strips will last for 3 to 4 winters.

For the current season, we have again equipped vehicles with the ice scraper carbon strip so that the control center can access the vehicles at any time if necessary."

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