Siemens SINUMERIK 840DE User Manual page 24

2 Connection Conditions
2.1 Secondary electrical conditions
3ph 400 V AC
N
Housing/shield
1
2
3
840D / 611 digital
G
Fig. 2-1 Safe isolation to EN 61800–5–1
Fig. 2-1 shows the various electrical potentials of the 840D/611D/S7-300 sys-
tem. Legend:
1. Floating power supply of the SIMODRIVE electronics unit with
2. Floating transistor triggers for the three-phase rectifier bridge with 230 V AC
3. Floating transistor triggers for each axis of the three-phase inverter bridge
4. Floating signal connection from the NCU to the PCU or HHU with 230 V AC
5. Non-floating signal connection between NCU and I/O devices.
6. Non-floating end user interface with protective separation for 230 VAC
7. Protectively separated 5 V DC power supply, fed from a protectively sepa-
8. 24 V DC power supply unit for external devices and for the machine adapta-
9. Floating interfaces to the machine (not accessible to the end user).
10. Floating signal interfaces directly accessible to the end user (e.g., V.24). For
11. 5 V DC power supply with basic insulation, fed from a safely-isolated
2-22
MSTT/MCP
4
11
4
HHU/
HT 6
Distribution box
4
5
10
5
Basic insulation Safety isolation
230 V AC basic insulation.
basic insulation.
with 230 V AC basic insulation.
basic insulation.
through interfaces 1 to 4 and 7.
rated 24 V DC supply.
tion control according to applicable standards in the form of a PELV (Protec-
tive Extra Low Voltage) circuit featuring safe isolation.
these interfaces, you must always make sure that there is either safe isola-
tion with respect to the line supply voltage or that there are two basic insula-
tion levels, for 230 V AC each.
24 V DC supply.
SINUMERIK 840D Configuring Manual NCU (PHD) – 03.06 Edition
PCU
24 V
4
11
6
S7-300 I/Os
10
Person
© Siemens AG, 2006. All rights reserved
03.06
8
G
7
Î Î
Motor
9
11
Terminal
block