Free tool
Siemens Part Number Decoder (MLFB)
Enter a Siemens order number and we'll identify the product family — S7 PLC, SINAMICS drive, SIRIUS contactor, HMI and more — and flag the lines that are obsolete.
Siemens identifies its products with an MLFB (order number) like 6ES7 314-1AG14-0AB0. The prefix tells you the product family at a glance, which is the key to identifying and sourcing the right part. Type your number above, then request a quote and we'll source it — including obsolete S7-300 and SINAMICS parts.
Common Siemens prefixes
The leading characters of the order number identify the family:
| Prefix | Product family |
|---|---|
| 6ES7 | SIMATIC S7 PLCs (S7-300, S7-400, S7-1200, S7-1500) and I/O |
| 6ES5 | SIMATIC S5 PLCs (legacy) |
| 6SL3 | SINAMICS drives / VFDs |
| 6SE7 | MICROMASTER / older drives (legacy) |
| 6SN | SIMODRIVE drives (legacy) |
| 6AV | SIMATIC HMI panels |
| 6GK | SCALANCE / industrial networking |
| 6EP | SITOP power supplies |
| 6ED | LOGO! logic modules |
| 3RT / 3RH | SIRIUS contactors & relays |
| 3RV / 3RW | SIRIUS motor protection & soft starters |
| 3VA / 3WL | SENTRON circuit breakers |
| 1FK / 1FT / 1PH | SIMOTICS motors |
Frequently asked questions
What is a Siemens MLFB number?
MLFB is the German abbreviation for Siemens' machine-readable product designation — the order number. It looks like 6ES7 314-1AG14-0AB0. The prefix identifies the product family; the middle encodes the specific type and ratings; the final block is the hardware/firmware revision.
Can you fully decode every digit?
Not reliably. Field positions differ between families and Siemens removed the public MLFB key around 2018, so much position-by-position detail online is community-derived. This tool identifies the family with confidence; for an exact decode and lifecycle status, confirm the full number on the Siemens SiePortal / Industry Mall.
What does the suffix like -0AB0 mean?
The final segment generally indicates a hardware revision or firmware/version state of an otherwise identical part. When sourcing, always quote the complete order number including the suffix so the replacement matches.
Need a Siemens part sourced?
Send us the order number — including obsolete S7-300 modules, SINAMICS drives or SIRIUS components — and we'll identify it and quote availability, condition and price.