A new standard DC filter called the FMER SOL from Schurter (Santa Rosa, CA) is designed for use on the DC side of the inverter in photovoltaic systems, and ensures EMC compliance and overall reliability of the entire PV system.

Maximum power point (MPP) trackers generate disturbances into the grid's AC power line as well as the DC side of the solar module. An AC filter is typically used on the grid's AC power line, but the noise generated on the DC side tends to be overlooked. EMC standards EN61000-6-3 and EN55014-1 also place strict limits on the noise generated downstream from the grid, and using the FMER SOL DC filter on the DC side of the inverter ensures EMC compliance.

The FMER SOL DC filters provide high temperature resistance to simplify cooling systems of large solar inverters, and reduce the energy needed to cool. The filters are designed for rated currents from 25 A to 1500 A at 55°C ambient temperature, and voltages up to 1200 VDC. Equipped with screw clamps for types up to 150 A and copper bars for types upwards of 250 A, other types of connections are available upon request.