General Principles

General Considerations for EMC-Conforming Assembly and Construction

Electric and electronical devices have to work correctly on site. This is also valid when electro-magnetic influences affect them in defined and/or expected strength. The devices themselves must not emit electro-magnetic noises.

Advant Controller components are developed and constructed so that they have a very high noise immunity. When the wiring and earthing instructions are met, an error-free operation is given.

However, there are applications where high electro-magnetic noises must be taken into due consideration already during the planning phase: e.g. when frequency converters, compressors, small-power pumps (high inductance) or mediumvoltage switchgear are mounted nearby. An EMC-compatible earthing concept will also guarantee an error-free operation here.

There are three important principles to be especially considered:

• Keep all connections as short as possible (in particular the earthing conductors)
• Use large conductor cross sections (in particular for the earthing conductors)
• Create low-impedance, i.e. good and large-sized contacts (in particular for the earthing conductors)

In particular:

• vibration-resistant connections
• clean metallic contact areas (remove paint, clean surfaces)
• if possible, do not use aluminium parts (they oxidize)
• solid plug and screw-type connections
• earth cable shields with clips on a well-grounded metallic surface
• do not use sheath wires
• do not use toothed lock washers under screw connections

Make a connection between the DIN rails and PE (Protective Earth). For this, use an earthing wire with a minimum conductor cross section of 10 mm². The wire is connected to the DIN rail with an M6 screw according to the drawing above. A large-area contact of the DIN rail with the metallic mounting plate improves the EMC behaviour significantly, as the disturbances can be discharged more effective.