Transmitter Interface - As-I Safety At Work - Siemens SIMATIC FS400 Anleitung

7.4.1 Transmitter interface - AS-i Safety at Work

The transmitter is only supplied with voltage via the AS-i cable. The transmitter does
not have an AS-i address. It can also be optionally operated with 24 V DC (as with
standard devices).
The transmitter device burdens the AS-i network with impedance, with use of a
SIMATIC FS400 3SF7842 - AS-i Safety at Work system an address should therefore
remain free per system (transmitter + receiver) for taking the transmitter impedance
into account (example: 2 SIMATIC FS400 3SF7842 - AS-i Safety at Work (corresponds
with 4 AS-i slaves and 27 standard slaves).
TEST TEST
IN
+24V GND OUT
a
AS-i +
AS-i -
a = Decoupling electronics
Fig. 7.4-2: Transmitter interface - AS-i Safety at Work, schematic structure
As a protective measure against damage caused by electrostatic discharge of the
device it is recommended that the housing profile of the device be earthed.
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