Siemens SIMATIC ET 200SP Manual page 19

Connecting
3.1 Pin assignment
Pin assignment of BaseUnit
The table below shows the terminal assignment, using the BaseUnit BU15-P16+A0+2B as an
example.
Table 3- 1 Terminal assignment of the BaseUnit BU15-P16+A0+2B
Designation
Channel 0
Pulse signal P/A
Pulse signal D/B
DQ Enable Drive
DI Reference Switch
DI Measuring Input
DI Drive Ready
Supply voltage and ground of
both channels
Ground for digital outputs,
digital inputs and pulse sig-
nals of the technology mod-
ule
24 V DC supply voltage
Behavior of the digital outputs following a wire break at the ground connection of the outputs
Due to the characteristics of the output driver used in the module, a wire break causes
approximately 10 mA supply current to drain from the digital outputs via a parasitic diode.
This behavior may lead to a high signal state even at outputs that are not set. Depending on
the nature of the load, 10 mA may be enough to activate a load with high signal state.
Duplicate wiring of ground
To prevent unintended switching of the outputs in the event of a ground connection wire
break, follow these steps:
1. Route the first ground connection from terminal M to the ground connection of the central
power supply of the plant.
2. Route the second ground connection from terminal 16 to the ground connection of the
central power supply of the plant.
If one of the two ground connection cables is interrupted, the outputs are maintained at the
required potential by the remaining ground connection.
Wire break at ground connection
Always connect two cables to the ground connection of the central power supply of the
system.
18
Signal name
CH0.P/A 1
CH0.D/B 3
CH0.ED 5
CH0.RS 7
CH0.MI 9
CH0.DR 11
M 13
M 15
L+
WARNING
View Signal name
2 CH1.P/A
4 CH1.D/B
6 CH1.ED
8 CH1.RS
10 CH1.MI
12 CH1.DR
14
16
Technology module TM PTO 2x24V (6ES7138‑6EB00‑0BA0)
Equipment Manual, 09/2021, A5E50983437-AA
Designation
Channel 1
Pulse signal P/A
Pulse signal D/B
DQ Enable Drive
DI Reference Switch
DI Measuring Input
DI Drive Ready
Ground of both channels
M Ground for digital outputs,
digital inputs and pulse sig-
M
nals of the technology mod-
ule
M Ground for supply voltage