Chapter 1 Introduction MS300 (High Speed Model) 1-4 RFI Jumper (1) In the drive there are Varistor / MOVs, which are connected from phase to phase and from phase to ground, to protect the drive against mains surges or voltage spikes. Because the Varistors / MOVs from phase to ground are connected to ground via the RFI jumper, the protection will be ineffective when the RFI jumper is removed. (2) In the models with built-in EMC filter the RFI jumper connects the filer capacitors to ground to form a return path for high frequency noise to isolate the noise from contaminating the mains power. Removing the RFI jumper strongly reduces the effect of the built-in EMC filter.
(3) Although a single drive complies with the international standards for leakage current, an installation with several drives with built-in EMC filter can trigger the RCD. Removing the RFI jumper helps, but the EMC performance of each drive would is no longer guaranteed. Frame B~F Screw Torque: 4~6 kg-cm / [3.5~5.2 lb-in.] / [0.39~0.59 Nm] Loosen the screw and remove the RFI Jumper (as shown below). Fasten the screw again after the RFI Jumper is removed. Frame B~F (model with built-in EMC filter) Remove the RFI Jumper with a screwdriver (as shown below). 1-4