Siemens PLC I/O Module SM 1221 Digital 28.8V
- RS Stock No.:
- 787-7945
- Distrelec Article No.:
- 110-48-544
- Mfr. Part No.:
- 6ES7221-1BH32-0XB0
- Brand:
- Siemens
Subtotal (1 unit)*
£217.15
(exc. VAT)
£260.58
(inc. VAT)
FREE delivery for orders over £50.00
Temporarily out of stock
- 6 unit(s) shipping from 11 May 2026
Need more? Click ‘Check delivery dates’ to find extra stock and lead times.
Units | Per unit |
|---|---|
| 1 + | £217.15 |
*price indicative
- RS Stock No.:
- 787-7945
- Distrelec Article No.:
- 110-48-544
- Mfr. Part No.:
- 6ES7221-1BH32-0XB0
- Brand:
- Siemens
Specifications
Technical Reference
Legislation and Compliance
Product Details
Find similar products by selecting one or more attributes.
Select all | Attribute | Value |
|---|---|---|
| Brand | Siemens | |
| Product Type | PLC I/O Module | |
| Module Type | Digital I/O Module | |
| Input Type | Digital | |
| Maximum Supply Voltage | 28.8V | |
| Number of I/Os | 16 | |
| Maximum Operating Temperature | 60°C | |
| Depth | 75mm | |
| Length | 100mm | |
| Standards/Approvals | cULus, CSA, CE, UL, FM | |
| Series | SM 1221 | |
| Width | 45 mm | |
| Select all | ||
|---|---|---|
Brand Siemens | ||
Product Type PLC I/O Module | ||
Module Type Digital I/O Module | ||
Input Type Digital | ||
Maximum Supply Voltage 28.8V | ||
Number of I/Os 16 | ||
Maximum Operating Temperature 60°C | ||
Depth 75mm | ||
Length 100mm | ||
Standards/Approvals cULus, CSA, CE, UL, FM | ||
Series SM 1221 | ||
Width 45 mm | ||
- COO (Country of Origin):
- DE
Siemens PLC I/O Module, Digital Input Type, 16 Inputs - SIMATIC Series - 6ES7221-1BH32-0XB0
This PLC I/O module from Siemens is designed to increase the range of your SIMATIC S7-1200 programmable logic controller. Use it to build a modular CPU system that meets your specifications with no redundant equipment. It features 16 digital inputs, so you can adapt the controller as needed to various industrial automation, robotics or manufacturing tasks. For flexible operation, it can be connected with both sink and source configurations. Galvanic isolation between digital inputs (in groups of four) allows information transfer while preventing current leakage and protecting your equipment.
• Compact dimensions of 75 (L) x 45 (W) x 100mm (H) saves space on the control panel
• Operating temperature range of -40°C to +70°C for use in challenging environments
• DIN rail mounting enables easy installation
How do I know if this module is working properly?
For straightforward troubleshooting, LEDs on the front panel show input status at a glance. A built-in alarm provides quick notification in the event of a fault, and the system also supports messaging for diagnostic functions and monitoring the supply voltage.
Related links
- Siemens SM 1223 Series PLC I/O Module for Use with SIMATIC S7-1200 Series Digital
- Siemens SIMATIC S7-1200 Series PLC Expansion Module for Use with S7-1200 Series, Digital
- Siemens PLC I/O Module for Use with SIMATIC S7-1200 Series Digital
- Siemens TM3 Series PLC I/O Module for Use with SIMATIC S7-1200 Series Digital, 24 V
- Siemens SM 1221 Series Digital Output Module for Use with S7-300 Series 230 V
- Siemens SM 1221 Series Digital I/O Module for Use with S7-300 Series Digital, 24 V
- Siemens SM 1223 Series PLC I/O Module for Use with SIMATIC S7-1200 Series Digital, 24 V
- Siemens SM 1231 Series PLC I/O Module for Use with SIMATIC S7-1200 Series Analogue, 24 V

