Features:
- A wide-range AC or DC input feeds the SIMATIC S7-400 rack supply.
- The 5 V backplane output delivers up to 20 A to installed rack modules.
- A separate 24 V DC output serves the documented auxiliary circuit.
Input conversion and rack distribution remain inside the two-slot power-supply module.
The backplane carries the regulated 5 V supply to the CPU and other S7-400 modules.
Status indicators and the optional battery path expose different supply and backup conditions.
The Siemens 6ES7407-0RA02-0AA0 SIMATIC S7-400 PS 407 20 A Power Supply Module may still be available for purchase and support from Apter Power beyond End-Of-Life (EOL) by the manufacturer (OEM).
Siemens 6ES7407-0RA02-0AA0 PS 407 Power Supply Module Manuals,Datasheets,Link
Important Notice: Other accessories, manuals, cables, calibration data, software, etc. are not included with this equipment unless listed in the above stock item description. All prices are shown in USD.
Following energy from the supply terminals to the S7-400 backplane
- Input stage: The documented AC or DC source enters through the front supply terminals.
- Conversion stage: Internal conversion produces the regulated rack voltage.
- Backplane feed: The 5 V output is distributed to modules through the rack connector.
- Load total: The sum of installed module currents must remain within the 20 A output.
Keeping the 24 V auxiliary circuit separate from the rack feed
- Output purpose: The front 24 V terminal serves its documented auxiliary load.
- Current limit: The connected circuit must remain within the 1 A rating.
- Reference path: Return wiring belongs to the assigned auxiliary-output terminals.
- Rack distinction: The auxiliary output does not replace the 5 V backplane supply.
Relating brief input loss to rack backup behavior
- Input buffering: Stored energy maintains the rack output for the documented interruption time.
- Battery option: Installed backup batteries support the defined S7-400 backup function.
- Polarity check: Battery orientation must match the marked holder.
- Service boundary: Battery condition and external input faults produce different indications.
Using front LEDs to separate supply conditions
- Rack output: The output indicator confirms the regulated backplane supply state.
- Input fault: Loss of the incoming source changes the associated status.
- Battery status: A separate indication identifies a missing or depleted backup battery.
- Fault response: The LED pattern should be compared with the rack diagnostic condition before modules are removed.