Part of the Siemens Siemens PLCs family.
Overview
S7-400 is the heavy-duty SIMATIC platform for large plants and process applications.
Within the Siemens PLCs family, SIMATIC S7-400 part numbers carry the 6ES74 prefix. Palm Parts Solution catalogs 2 distinct SIMATIC S7-400 part numbers, classified across 2 product types (Digital Input Modules, Digital Output Modules).
The catalogued part numbers are 6ES7421-1BL01-0AA0, 6ES7422-1BL00-0AA0.
SIMATIC S7-400 parts
Specifications
| Field | Value |
|---|---|
| Manufacturer | Siemens |
| Product family | Siemens PLCs |
| Series | SIMATIC S7-400 |
| Part-number prefixes | 6ES74 |
| Distinct part numbers catalogued | 2 |
| Product types represented | 2 |
| Condition | New, Refurbished, or Surplus (varies by listing) |
Part numbers by product type
- Digital Input Modules — 1 part number catalogued (6ES7421-1BL01-0AA0)
- Digital Output Modules — 1 part number catalogued (6ES7422-1BL00-0AA0)
Compatible series
Product types in this series
Frequently asked questions
What does the SIMATIC S7-400 series include?
The SIMATIC S7-400 series is part of the Siemens PLCs family from Siemens. It groups related catalog numbers that share form factor, I/O type and communication protocol — making it easy to find drop-in replacements.
Is SIMATIC S7-400 compatible with newer Siemens hardware?
In most cases yes. SIMATIC S7-400 units interoperate with current Siemens programming software and communication backbones. Contact us with your firmware revision and we will confirm before shipping.
Can I get SIMATIC S7-400 parts refurbished with warranty?
Yes. We offer refurbished SIMATIC S7-400 modules tested to OEM specs with a 1-year replacement warranty. New surplus stock is also available when supply permits.
Machine down? Get a fast quote on the parts you need.
New, surplus, and refurbished industrial automation options. Request a quote or speak directly with an automation specialist for emergency sourcing.