Siemens S7-300 - Page 187

Analog modules
9.2 SM 336; AI 6 x 13 Bit
Fail-safe signal modules
Installation and Operating Manual, 01/2010, A5E00085586-10
187
Sensor supply
WARNING
Voltage dips of the power supply are not buffered by the module and, thus, affect the
sensor supply.
This can cause the measured value to be false.
You can avoid voltage dips by using a voltage supply according to the NAMUR
recommendation (see Chapter " Safe Functional Extra-Low Voltage for Fail-Safe Signal
Module
s (Page 44) "). Alternatively, use
a transducer with an appropriate battery
backup or
diagnostics.
External sensor supply
The figures below shows how you can supply power to the sensors by means of an external
sensor supply (for example, from another module: 1L+).
96

0
0
0$1$

60
$,[%LW
/
0
3
'08
0
/
UHFRPPHQGHG
Figure 9-5 External encoder supply, 2-wire transducer for SM 336; AI 6 x 13Bit
/
0
96

0
0
0$1$

60
$,[%LW
'08
3
0
/
UHFRPPHQGHG
6HQVRU
IRUH[DPSOHSUHVVXUHJDJH
Figure 9-6 External encoder supply, 4-wire transducer for SM 336; AI 6 x 13Bit