As the number of electric vehicles increases, the expansion of the charging infrastructure is also increasing in order to create sufficient charging options for electric vehicles. In addition to charging at home, charging at work also plays an important role. AC charging stations are often set up in employee parking lots and connected directly to the industrial grid due to long parking and charging times. This allows existing power reserves to be used and costs to be reduced. This direct integration means that existing harmonic sources from the production grid come into contact with new harmonic sources in the form of electric vehicles, which interact with each other and can increase the harmonic load. This can have a negative impact on production. It makes sense to assess the extent to which electric vehicles affect the production grid before integrating the charging infrastructure. In this publication, measurements carried out on an employee parking lot are evaluated and the results presented.