Siemens 353 - DIN - Digital Inputs

UM353-1B Function Blocks
April 2012
3-35
3.2.28 DIN_ - Digital Inputs
DIN_ function blocks can be used to sense a discrete
signal from an external source and provide a block output
representing the state of this signal. Blocks are available
on the Controller Board and on the Expander Board.
Function block names (IDs) and terminal designators are
listed in Section 7.4 Electrical Installation.
The block output is high (1) when the input is on and low
(0) when off.
Output QS indicates the quality status of the output signal
O1 and will be high (1) when the output is of bad quality.
Bad quality indicates any hardware failure of the input
converter.
DIN_+
DIN_-
DIGITAL INPUT _
DIGITAL INPUT
DIN_
O1
O
utput
1
QS
Q
uality
S
tatus
BLOCK DIAGRAM
O1
Typical External
Circuit
24 Vdc
-
+
A/D
QS
Quality Test
DIN_-
DIN_+