Download CFC Changes to an S7-400H in RUN with a Flash EPROM Card

For S7-400H applications that require user-program editing in RUN, Siemens' S7-400H System Manual specifies a RAM card. It describes Flash as nonvolatile program storage and a Flash loading sequence that places the CPU in STOP. A redundant CPU 414-5H system using 16 MB Flash EPROM cards should therefore not assume routine CFC changes can be downloaded in RUN; verify the exact CPU, card, firmware and PCS 7 V9.0 SP3 procedure.

Memory-card choice

The opened S7-400H System Manual distinguishes RAM and Flash: it says to use RAM if the program must be edited in RUN, and describes Flash as nonvolatile storage. It also documents loading individual program elements to RAM in STOP or RUN. Its Flash-loading sequence starts by placing the CPU in STOP.

Apply the distinction to this setup

The reported pair used CPU 414-5H processors and 16 MB Flash EPROM cards with PCS 7 V9.0 SP3. That hardware description does not match the manual's stated card selection for RUN editing. It does not prove that every 414-5H/firmware combination has identical restrictions or establish a supported card conversion.

Incremental and full downloads

The source replies say small CFC changes can differ from first/full downloads and that structural interface changes or online/offline timestamp mismatch can prevent an incremental change. Treat these as reported guidance; confirm exact eligibility and CFC/SFC loading steps in PCS 7 V9.0 SP3 documentation. Do not use HW Config STOP/RUN controls as a substitute for program loading.

Decision procedure

Record CPU order number and firmware, memory-card type/order number, PCS 7/CFC release and the exact compile/download message.
Determine whether the change qualifies for incremental loading or requires a full download.
Check project/online consistency and interface changes.
Use the documented PCS 7 loading operation for the installed release and redundant CPU pair.
If the card type conflicts with RUN editing, stop and get a supported hardware strategy before touching the running pair.

Verification

After an approved change, check online/offline consistency, CPU redundancy state, expected block execution, process values and alarms. A download acknowledgement alone does not confirm correct plant behavior.

Limitations and Operational Precautions

The memory-card reference is the 2010 S7-400H manual, not a complete PCS 7 V9.0 SP3 CFC procedure. Firmware, card MLFB, exact diagnostic text and test result were not supplied. Back up and follow site-approved outage and rollback controls.

Engineer FAQ

Can Flash and RAM cards be treated the same for RUN editing? No. The cited manual states RAM for program editing in RUN and Flash for nonvolatile retention.

Does this prove every Flash-based 414-5H can never accept any RUN change? No. Check the exact CPU firmware, card and PCS 7/CFC release documentation.

Technical References

S7-400H System Manual, 12/2010, A5E00267695-07, section 5.7, “Design and function of the memory cards,” pp. 53–54. Official Siemens PDF opened and read.
PCS 7 Readme V9.0 incl. SP2 describes the CFC/SFC loading functions used for RUN-mode downloads; direct retrieval returned 403 and this is not a substitute for V9.0 SP3 instructions.