Technical data

PD_OpManPS-4_05_us.fm
page 30 PacDrive PS-4 / PD-8 ELAU AG
5 Maintenance
Hard-copy for correction
5.6 EMC Rules
To control and regulate motors, the mains voltage is stored in the
DC-circuit of the PS-4 by means of rectification. This DC-circuit
voltage supplies all connected SCL-055s. In the SCL-055, this
stored energy is fed to the motor by deliberately activating and
deactivating six semiconductor switches. The steep rise and fall of
the voltage puts high demands on the insulation strength of the
motor winding. Another essential aspect to be considered is Electro
Magnetic Compatibility (EMC) with other system components.
The
flank steepness of the clocked voltage generates harmonic
oscillation of great intensity, up into the high-frequency range.
Therefore observe the following EMC rules:
 Choose the grounding option with the lowest possible ohm rate
for the PS-4 (e.g. unpainted mounting board of switching
cabinet) for installation.
 Contact the largest possible surface (skin effect). If necessary,
remove existing paint to achieve large-surface contact.
 From the Central Earthing Point, lay the grounding wires to the
respective connections in a star structure. Earthing loops are not
allowed and can cause unnecessary distortions.
 Use shielded cables only.
 Only large-surface shield transitions are allowed.
 By all means observe the switching proposals.
 Do not lay any cable loops inside the switching cabinet.