Emc Measures Indracontrol Vch 08.1 - Bosch Rexroth VCH 08.1 Manual

DOK-SUPPL*-VCH*08.1***-PR02-EN-P
Rexroth IndraControl VCH 08.1 Hand-held Terminal
Prevention of couplings
4.14.4

EMC Measures IndraControl VCH 08.1

Shield connections
higher frequencies and therefore the material losses are responsible for the
attenuation and the interference is not reflected, as in the case of inductance,
but is converted into heat.
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S
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S
① Ferrite
② Data line
I Interference current
S
I Operating current
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Fig.4-37: Current flow for ferrites
Coupling between interference sensitive signals (e.g. analog signals) and the
lines that carry the interference signals (e.g. motor lines) can be reduced by
laying cables separately.
The IndraControl VCH 08.1 is designed for industrial applications. Considerable
electromagnetic and electrostatic interference can occur in this environment.
For this reason special emphasis was placed on noise immunity and data se‐
curity in the design of the device. The EMC design implemented and described
below considers all the above named sources of interference and the possible
coupling paths.
● All shielding and filter measures (filtered power supply) in the IndraControl
VCH 08.1 are carried out directly on the printed circuit board.
● The special design of the cable guarantees noise immunity even for great‐
er connection lengths. I.e. the data lines (communication signals) are
shielded and so they are separated from the control lines (power supply,
enabling button, emergency stop, key switch etc.) inside the cable.
● Power supply lines in the control cabinet are usually unshielded. They are
therefore laid outside the IndraControl VCH 08.1 cable shield in order to
prevent a coupling with the sensitive data lines.
● The unshielded control and power supply lines are either filtered on entry
into the shielded housing of the IndraControl VCH 08.1 or separated from
the electronics in such a way that any interference signals carried by these
lines cannot affect the internal electronics of the IndraControl VCH 08.1.
● It is not necessary to lay the IndraControl VCH 08.1 cable separately.
The cable shield of the IndraControl VCH 08.1 cable can be considered to be
an extension of the IndraControl VCH 08.1 shielded housing (=printed circuit
board), via the VAC connection box, to the shielded housing of the communi‐
cation partner (e.g.: a PLC). From this it can be deduced that the shielded
connections from the cable shield to the device shields substantially contribute
to the interference immunity of the IndraControl VCH 08.1. It is not necessary
to wire shielded connections to earth. The shield connection within the Indra‐
Control VCH 08.1 is realized via the cable shield, i.e. via the 17-pin connector.
Connecting the IndraControl VCH 08.1 via a connection module guarantees
safe shielding protection right through to the communication partner. All con‐
nection cables available from Bosch Rexroth guarantee a proper shield con‐
nection.
Bosch Rexroth AG
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Technical Data
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