Gantner e.bloxx A5CR, Руководство пользователя

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e.bloxx A5-1CR
MOUNTING e.bloxx AND CONNECTING WIRES
HB_EBLOXX-A5CR_E_V11.doc
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Gantner Instruments Test & Measurement GMBH
Notice:
It depends on the power supply unit and its noise and internal grounding issues whether it is helpful to
connect earth of the power supply unit with ground/earth of the e.bloxx module.
Picture 3.1. - Power Supply of the e.bloxx Modules
3.4. Bus Connection
Only the connection of the e.bloxx modules to the bus is described in here. A detailed description of the bus and the
communication of the modules can be found in the Communication Guide of the e.bloxx/e.gate modules.
The e.bloxx modules have an RS 485 bus interface for connection to the serial fieldbus. The bus has to be terminated
on both sides with a characteristic impedance. The maximum line length depends on the transmission speed (refer to
the Communication Guide for details) and can never be higher than 1.2 km per bus segment or 4.8 km via a physical
bus string by using 3 repeaters. A maximum of 32 devices are possible with each bus segment and up to 127 devices
via a physical bus string.
Wiring
In general, the e.bloxx is connected to the bus by connecting both signal leads A and B of the incoming bus cable and
A' and B' of the outgoing bus cable together to one terminal on the module (Picture 3.2). Alternatively, the bus can also
be connected by a "stub cable" (Picture 3.3). This guarantees that the bus connection to other modules remains in
place, even if one module has to be exchanged, due to the removable terminal strip.