Delta Compact Drive MS300 IP66/NEMA 4X Series, User Manual

Page: 11 / 135

Chapter 1 Introduction

MS300 (IP66 / NEMA 4X)
1-4
1-4 RFI Jumper
The drive contains Varistors/MOVs that 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 with the RFI jumper,
removing the RFI jumper disables the protection.
(1) In models with a built-in EMC filter, the RFI jumper connects the filter capacitors to ground to form a
return path for high frequency noise. This isolates the noise from contaminating the mains power.
Removing the RFI jumper strongly reduces the effect of the built-in EMC filter.
(2) Although a single drive complies with the international standards for leakage current, an installation
with several drives with built-in EMC filters can trigger the RCD. Removing the RFI jumper can help,
but the EMC performance of each drive is no longer guaranteed.
(3) Description for removing and connecting the RFI jumper.
Frame A–C (model without built-in EMC filter) Screw Torque: 4–6 kg-cm / [3.5-5.2 lb-in.] /
[0.39-0.59 Nm]
Loosen the screw (as shown in Figure 1-2) and turn the RFI jumper counterclockwise (as shown in Figure
1-3) to remove. Fasten the screw again after you remove the RFI jumper. To connect the RFI jumper,
loosen the screw and turn clockwise (the position of RFI jumper changes from Figure 1-3 to Figure 1-2).
Similarly, fasten the screw again after you connect the RFI jumper.
Figure 1-2
Figure 1-3