Bosch Rexroth VCH 08.1 Manual page 47

DOK-SUPPL*-VCH*08.1***-PR02-EN-P
Rexroth IndraControl VCH 08.1 Hand-held Terminal
Technical systems as interference
Coupling paths
Periodically occurring interference:
● Ignition impulses of combustion engines
● Sparking of commutator motors
● Electromagnetic fields of induction furnaces, arc welding devices, micro‐
wave ovens etc.
● Pulse currents from frequency converters and power modules
● Electromagnetic fields of radio and telecommunications devices
Randomly occurring interferences are:
● Ignition impulses of fluorescent lamps
● Switching procedures on inductive electrical circuits
● Contact bounces when closing or opening switching contacts
● Voltage fluctuations on heavy load switching procedures
There is a series of test standards for the above listed interference sources,
intentionally or unintentionally caused by technical systems, which simulate
these interferences:
● IEC 61000-4-3 High Frequency Electromagnetic Field Immunity Test
● IEC 61000-4-4 Electrical Fast Transient / Burst Immunity Test
● IEC 61000-4-6 Test of Immunity to Conducted Disturbances, Induced by
High Frequency Fields
● IEC 61000-4-8 Power Frequency Magnetic Field Immunity Test
● IEC 61000-4-11 Voltage Dips, Short Interruptions and Voltage Variations
Immunity Test
All the international standards listed here are also available as European stand‐
ards. The product standard IEC 61131-2 demands testing to these standards
and also defines the severity level.
In the case of functional interference, EMC problems first arise at interference
sinks
sinks. The following interference sinks can be identified dependent on the de‐
gree of immunity to electromagnetic influences:
Fig.4-32: Examples for technical systems as interference sinks
Control systems without integrated switching circuits are unthinkable and would
therefore not be sufficiently immune without suitable EMC measures.
The transfer of interference from an interference source to an interference sink
can take place via various coupling paths. Coupling paths very often exist of
Bosch Rexroth AG 45/117
Technical Data