Image is for illustrative purposes only. Please refer to product description.
- Manufacturer
- Siemens
- Manufacturer part number
- 6ES7321-1BL00-0AA0
- Product family
- SIMATIC S7-300 PLC Modules
- Category
- PLCs and I/O › Digital I/O modules
- Technical datasheet
- Data sheet
Specifications
| Attribute | Value |
|---|---|
| Type | Digital input module |
| Manufacturer lifecycle | Discontinued |
| Product function / Isochronous mode | No |
| Load voltage L+ / Rated value (DC) | 24 V |
| Load voltage L+ / permissible range, lower limit (DC) | 20.4 V |
| Load voltage L+ / permissible range, upper limit (DC) | 28.8 V |
| Input current / from backplane bus 5 V DC, max. | 15 mA |
| Power loss, typ. | 6.5 W |
| Number of digital inputs | 32 |
| Digital inputs / Input characteristic curve in accordance with IEC 61131, type 1 | Yes |
| Number of simultaneously controllable inputs / horizontal installation / up to 40 °C, max. | 32 |
| Number of simultaneously controllable inputs / horizontal installation / up to 60 °C, max. | 16 |
| Number of simultaneously controllable inputs / vertical installation / up to 40 °C, max. | 32 |
| Input voltage / Type of input voltage | DC |
| Input voltage / Rated value (DC) | 24 V |
Show all 44 specificationsShow fewer specifications
| Input voltage / for signal "0" | -30 to +5 V |
|---|---|
| Input voltage / for signal "1" | 13 to 30V |
| Input current / for signal "1", typ. | 7 mA |
| Input delay (for rated value of input voltage) / for standard inputs / parameterizable | No |
| Input delay (for rated value of input voltage) / for standard inputs / at "0" to "1", min. | 1.2 ms |
| Input delay (for rated value of input voltage) / for standard inputs / at "0" to "1", max. | 4.8 ms |
| Input delay (for rated value of input voltage) / for standard inputs / at "1" to "0", min. | 1.2 ms |
| Input delay (for rated value of input voltage) / for standard inputs / at "1" to "0", max. | 4.8 ms |
| Cable length / shielded, max. | 1 000 m |
| Cable length / unshielded, max. | 600 m |
| Connectable encoders / 2-wire sensor | Yes |
| Connectable encoders / 2-wire sensor / permissible quiescent current (2-wire sensor), max. | 1.5 mA |
| Interrupts/diagnostics/status information / Alarms | No |
| Interrupts/diagnostics/status information / Diagnostics function | No |
| Alarms / Diagnostic alarm | No |
| Alarms / Hardware interrupt | No |
| Diagnostics indication LED / Status indicator digital input (green) | Yes |
| Potential separation digital inputs / between the channels | No |
| Potential separation digital inputs / between the channels, in groups of | 16 |
| Potential separation digital inputs / between the channels and backplane bus | Yes; Optocoupler |
| Isolation tested with | 500 V DC |
| required front connector | 40-pin |
| Width | 40 mm |
| Height | 125 mm |
| Depth | 120 mm |
| Weight, approx. | 260 g |
| Phase-out announced (PM400) | 1 October 2023 |
| Product cancellation (PM410) | 1 October 2025 |
| Spare part | Yes, supplied by Siemens as a spare part only |
Description
The Siemens 6ES7321-1BL00-0AA0 is the SM 321 digital input module with 32 inputs at 24 V DC, IEC 61131 type 1 characteristic. Siemens's data sheet gives input delays of 1.2 to 4.8 ms, optocoupler isolation from the backplane bus in two groups of 16, 2-wire sensor support, and a 40-pin front connector for the field wiring; the module is 40 mm wide. Siemens's data sheet marks it as a spare part. Siemens names no direct successor for the order number; its route forward is migration to the S7-1500.
Application: Digital input module
Used with: SIMATIC S7-300 rack (S7-300 backplane bus)
What is the 6ES7321-1BL00-0AA0 used for?
It reads switches, sensors and contacts into an S7-300 CPU, in the CPU's rack or in an ET 200M remote station.
Key features
- 32 digital inputs, 24 V DC, IEC 61131 type 1
- Isolated from the backplane bus by optocoupler, groups of 16
- Input delay 1.2 to 4.8 ms
- Accepts 2-wire sensors
- 40-pin front connector
- Discontinued by Siemens on 1 October 2025; spare part only
Documents and Resources
Associated Products
| Image | Product | Description | Stock | View | Add to RFQ |
|---|---|---|---|---|---|
 | 6ES7322-1BL00-0AA0Siemens | SM 322 digital output, 32 DO, 24 V DC, 0.5 A | In stock | View | |
 | 6ES7321-1BH02-0AA0Siemens | SM 321 digital input, 16 DI, 24 V DC | In stock | View | |
 | 6ES7322-1BH01-0AA0Siemens | SM 322 digital output, 16 DO, 24 V DC, 0.5 A | In stock | View | |
 | 6ES7322-1HH01-0AA0Siemens | SM 322 relay output, 16 DO, relay contacts | In stock | View | |
 | 6ES7323-1BL00-0AA0Siemens | SM 323 digital I/O, 16 DI and 16 DO, 24 V DC | In stock | View | |
 | 6ES7321-1FH00-0AA0Siemens | SM 321 digital input, 16 DI, 120/230 V AC | In stock | View | |
 | 6ES7322-1FH00-0AA0Siemens | SM 322 digital output, 16 DO, 120/230 V AC, 1 A | In stock | View | |
 | 6ES7322-1HF01-0AA0Siemens | SM 322 relay output, 8 DO, relay contacts | In stock | View | |
 | 6ES7321-7BH01-0AB0Siemens | SM 321 digital input, 16 DI, 24 V DC, diagnostics and hardware interrupt | In stock | View | |
 | 6ES7321-1BH50-0AA0Siemens | SM 321 digital input, 16 DI, 24 V DC, sourcing input | In stock | View | |
 | 6ES7321-1FF01-0AA0Siemens | SM 321 digital input, 8 DI, 120/230 V AC | In stock | View | |
 | 6AG1321-1BL00-2AA0Siemens | SIPLUS SM 321 digital input, 32 DI, 24 V DC, conformal coating | In stock | View |
Product Questions
Is the 6ES7321-1BL00-0AA0 discontinued?
Yes. Its manufacturer lifecycle status is Discontinued.
Can another Siemens SIMATIC S7-300 part replace it?
Potential replacements must be checked against the required ratings, dimensions and connections. Sharing a family name does not establish interchangeability.
Do you ship worldwide?
Yes. TimControls ships worldwide. Parts usually ship within 3 to 7 working days of order confirmation, and the exact lead time and shipping options are stated on your quote. Include your delivery country and postal code when you ask for a quote.
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