Operating instructions

MICRO PANEL XV-102 3.5" 5. Installation

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RS485 topology #

# A bus segment can connect up to 32 bus stations.

# Several bus segments can be linked via repeaters (bidirectional amplifiers). Refer to the documen-

tation of the repeater manufacturer for further information.

# A bus segment must be provided with cable termination (120 Ω) at both ends. These terminations

must be connected directly between pin 3 and 7 in the connector.

The maximum cable length can be increased by using repeaters. Refer to the documen-

tation of the repeater manufacturer for further information.

# The bus segment must be terminated at both ends.

# No more than two terminations must be provided on each bus segment.

# Transmission faults can occur if operation is carried out without the correct termina-

tion.

Fig. 16 Termination

120