The electromagnetic compatibility (EMC) and interference (EMI) challenges during the development, construction, testing and installation of a measurement system for multi-point, high-speed and long-term data logging is described in this paper. The presented measurement system was tested in a rough offshore environment at Avedøre Holme and Gunfleet Sands offshore wind farms. The paper clearly presents possible electromagnetic interference in wind turbines that can affect measurements. Also the application of appropriate mitigation techniques such as data acquisition board configuration, coaxial cable leading, as well as usage of EMC-proof boxes for high frequency measurements is described. Some measurement results focused on dealing with EMI are also presented and explained.