Infranor Xtracontrol DC2, Руководство пользователя

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User Manual V1.3 | XtracontrolDC2, XtracontrolET2, XtracontrolEC21
Signal interference and terminating resistor
To minimise interference, the following instructions must be complied with.
Actively driven bus
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An appropriate protocol must be employed to ensure that at all times one of the bus participants is actively
driving the bus.
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For a highly symmetrical signal-noise ratio the bus must have defined statuses for logical “1” (A–B < –0.2 V)
and logical “0” (A–B > +0.2 V).
Undriven bus
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The bus termination must be as asymmetric as possible to ensure the greatest possible signal-noise ratio (to
reduce the symmetrical signal-noise ratio).
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In order to achieve the necessary voltage difference between the signals, a suitable resistor network must be
used as the line termination.
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The necessary size of the resistors is governed by the bus length and transmission rate (similarly to the line
termination for Profibus, see DIN EN 61158-2).
Connections with GND
To minimise common-mode interference or malfunctions due to potential differences:
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Check the topology and line lengths to determine whether additional connection to GND are necessary.
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For electrically isolated interfaces with connections to the reference ground at one point: link to GND.
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Where necessary, provide an attenuated link to GND (e.g. via 200 ) at multiple points.
Ω
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