Operating Instructions; Scope Of Application; General Data; Data Transfer - Siemens 7XV5450 0BA00 Operating Instructions Manual

1.9

Operating Instructions

1.9.1

1.1 Scope of Application

The Mini Starcoupler is used for optical connection of up to four terminal units with an
optical interface in a star topology to a master unit for centralized operation, thus
allowing to establish an inter-ference- immune connection between the field devices
and the centralized operating unit. Direct communication between a PC and the
terminal units is possible via the integrated RS232 interface.
1.9.2

General Data

The starcoupler is equipped with one optical PC input and output and
4 optical inputs and outputs to the terminal units. Cascading of the star coupler is
possible. The Mini-Starcoupler has a plastic housing that can be snapped onto a DIN
EN 50022 rail. The auxiliary power supply is fed in via terminals on one side of the
housing. Because of its extremely wide power supply range (DC 24 - 250 V and AC
60 - 250 V), the Starcoupler can be connected without switchover to all common
types of station batteries and AC mains voltage supplies.
The readiness for service of the unit is indicated by means of a potential-free
signalling contact (terminals 1,2) that can be used to communicate the following fault
conditions to a control center:
 No supply voltage
Failure of internal power supply
When a fault condition is present, the contact is closed.
1.9.3

Data Transfer

Operation of the mini starcoupler is transparent and full-duplex. Data received from
the master unit are forwarded by the receiver of channel 1 to all outputs (channels 2,
3, 4 and 5). Data from one of the outputs (channel 2, 3, 4 and 5) are sent to the
transmitter of channel 1. The logic of the optical interfaces is positive (Light OFF in
idle state), incoming light signals are treated as active = 1 (high). For use in systems
operating with a negative logic, the starcoupler can be switched over to negative logic
by means of a switch that is accessible from outside. Inversion of the logic applies to
both the optical input and the optical output of this interface. On delivery, the
starcoupler is set to positive logic (Light OFF in idle state). When set to negative
logic, the receiver must have light in idle state, otherwise the starcoupler is blocked.
7XV5450-0BA00 Mini-Star coupler
C53000-B1140-C595-1
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