Serie 750, 753
System Features
System manual | Version: 3.0.2
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3.2.3 Field Supply
Figure 13: Field Supply Input (example)
Observe the following requirements for the field supply:
• Use voltage sources with safe extra-low voltage (SELV, PELV) for all voltages with a
nominal value of 24 VDC.
• Be sure to include an overcurrent protection device to ensure the maximum permissi-
ble current values are not exceeded.
Additional supply modules are needed for:
• Higher power requirements
• Use of different potential groups
• Use of different field voltages
• Functional change (e.g., Ex i or functional safety)
3.2.4 Power Supply Components
The following components are needed to establish a power supply:
•
Voltage Sources with Safe Extra-Low Voltage (SELV, PELV)
•
Overcurrent protection devices
– Supply modules with integrated fuses
– External fuse terminal blocks
– Circuit-breakers
•
Suitable isolation devices,
e.g., non-automatic circuit-breaker
•
Supply modules
– Bus power supplies
– Supply module
