Gantner e. Series, Руководство пользователя

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e.bloxx A9-1
MOUNTING e.bloxx AND CONNECTING WIRES
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HB_EBLOXX-A9_E_V13.doc
Gantner Instruments Test & Measurement GmbH
Picture 3.2. - Bus Connection of an e.bloxx A9-1 to the RS-485 Fieldbus with Derivation
Picture 3.3. - Bus Connection of an e.bloxx A9-1 to the RS-485 Fieldbus via Stub Cable
The stub-cable should be as short as possible, not longer than 30 cm.
Notice:
The terminal designations A and B of all modules of the e.bloxx series are exchanged compared with the
PROFIBUS-definitions. Consequently, in multi-vendor systems the bus lines A and B have to be exchanged
when connecting them to the e.bloxx.
Bus Structure
The bus structure is a line structure where each bus segment will be terminated with an characteristic impedance on
both ends. Branches can be set up by means of a bi-directional signal amplifier, so-called repeaters. Other types of
branches are not permitted (no tree topology). The max. stub-length to a user may not exceed 30 cm.
The following figures show a few examples of possible bus topology structures. The meanings of the symbols are as
follows: