Siemens Simatic 6ES7 157-0AC80-0 A0 Series, Руководство пользователя

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Wiring
4-11
DP/PA Link and Y Link Bus Couplings
A5E00193841-011
Bus terminating resistors
The Y coupler does not contain integrated bus terminating resistors. When the Y
coupler is arranged at the beginning or end of a bus segment, the bus terminating
resistors on the bus connector must be connected.
4.3 Connecting the power supply
The power supply is connected in the same manner for all described modules.
The connections that must be established between a power supply and
components are described in the subsections 4.2.1 to 4.2.4.
Required tool
To connect the power supply, you require a 3 mm screwdriver.
Power supply unit
You can only use power supply units of the type SELV with safe, electrically
isolated functional, extra-low (
v
60V DC) voltage.
The size of the power supply unit depends on the current consumption of the
connected components (see Appendix B, Technical Data).
Power supply connection
The 4 pin screw-type terminal for the 24V voltage supply is found on the IM 157
behind the front door at the bottom. The connections have the following functions:
M
L+
M
Functional ground
Removable bridge for
ungrounded configuration
(see Section 4.1.3)
Ground
+24 V DC
Ground
Figure 4-8 Power supply for IM 157
The maximum conductor cross-section is 2.5 mm
2
. There is no cable grip.