Siemens SINUMERIK ONE PPU 1740 Series Equipment Manual page 72

Interface description
7.4 Digital inputs/outputs
Connecting the inputs and outputs:
● Recommended connection: Inputs and outputs connected to the same supply
If both inputs and outputs are operated with the same 24 V supply.
● Not recommended connection: Inputs and outputs on different supplies
X242 pin assignment
Pin
1
2
3
4
5
6
7
8
9
10
11
72
NOTICE
Exceeding the permissible input current
If the inputs and outputs are supplied separately with power, the input current can exceed
the permissible value of 15 mA according to EN61131-2, and the signal source can be
overloaded.
Signal name
Not connected
Not connected
IN1 DIN1
IN2 DIN2
IN3 DIN3
IN4 DIN4
M4 MEXT4
P3 P24EXT3
O1 DOUT1
O2 DOUT2
M3 MEXT3
NC variable Meaning
$A_IN[1] Digital NC input 1
$A_IN[2] Digital NC input 2
$A_IN[3] Digital NC input 3
$A_IN[4] Digital NC input 4
Ground for pins 3...6
+24 V power supply
$A_OUT[1] Digital NC output 1
$A_OUT[2] Digital NC output 2
Ground for pins 9, 10, 12, 13
Equipment Manual, 01/2019, A5E47615272B AA
PPU 1740