Installation Guidelines
S5-115F Manual
3.4.2
Electrical Installation with Field Devices
The following figures each show an example circuit for connecting control power supply and load
power supply. They also show the grounding concept for operation from the following:
•
Grounded supplies
•
Centrally grounded supplies
•
Nongrounded supplies.
Please note the following when installing your controller. The text contains reference numbers
which you can find in Figures 3-30 to 3-32.
Master switch and short-circuit protection
•
You must provide a master switch to DIN VDE 0113, Part 1, or a disonnecting device to DIN
VDE 0100, Part 460, for the programmable controller, sensors and actuators.
These devices are not required in the case of subsystems where the relevant device has been
provided at a higher level.
•
You can provide the circuits for sensors and actuators with short-circuit protection and/or
overload protection in groups. According to DIN VDE 0100, Part 725, single-pole short-
circuit protection is required in the case of grounded secondary side and all-pole protection is
required in all other cases.
•
For nonfloating input and output modules, connect terminal M of the load power supply unit
with the PE ground conductor of the control circuit's PS 951 power supply module.
Load power supply
•
For 24 V DC load circuits, you require a load power supply unit with safe electrical isolation.
•
You require a back-up capacitor (rating: 200
µ
F per 1 A load current) for nonstabilized load
power supply units.
•
For controllers with more than five electromagnetic operating coils, galvanic isolation by a
transformer is required by DIN VDE 0113, Part 1; it is recommended by DIN VDE 0100, Part 725
.
•
For nonfloating input and output modules, connect terminal M of the load power supply unit
with the PE ground conductor of the control circuit's PS 951 power supply module.
3-34
EWA 4NEB 811 6148-02
