1. Sensors Industrial Automation Control For Sale
  2. sku: 21159341970059713
  3. SIEMENS 6ES5751-3AA12

SIEMENS 6ES5751-3AA12 Plc Modules

6es5751-3aa12 Siemens / 6es57513aa12 Used

( Brand: Siemens ), ( Manufacturer Part Number: 6ES5751-3AA12 ), ( Part Type: Module )

Review SIEMENS 6es57513aa12 Used

The **Siemens 6ES5751-3AA12** is a high-performance, modular **SIMATIC ET 200SP** (S7-1200/1500-compatible) terminal block designed for industrial automation applications requiring robust, space-efficient, and flexible connectivity solutions. Part of Siemens extensive **ET 200SP** series, this terminal block is engineered to meet the stringent demands of modern manufacturing, process control, and automation environments where reliability, compactness, and ease of integration are paramount. With a **12-pin configuration**, it provides a versatile interface for connecting discrete signals, analog inputs/outputs, or digital communication lines to a control system, making it an ideal choice for both new installations and retrofitting existing setups.

Constructed from high-quality, corrosion-resistant materials, the **6ES5751-3AA12** terminal block ensures long-term durability in harsh industrial conditions, including exposure to temperature fluctuations, moisture, and electromagnetic interference. Its **modular design** allows for seamless integration into Siemens **ET 200SP** system architecture, where it can be paired with other compatible terminal blocks, power supplies, and I/O modules to create a scalable and adaptable control solution. The block features **screw-type terminals**, providing secure and reliable connections that minimize signal degradation while simplifying installation and maintenance. Each terminal is clearly labeled, ensuring quick identification and reducing the risk of wiring errors during commissioning.

One of the standout features of the **6ES5751-3AA12** is its **compact footprint**, which is critical in space-constrained environments such as control cabinets, panel-mounted systems, or distributed I/O applications. The terminal block s **low-profile design** allows for efficient cable management, reducing clutter and improving accessibility for technicians. Additionally, its **compatibility with Siemens TIA Portal** software ensures seamless integration with SIMATIC S7-1200 or S7-1500 PLCs, enabling engineers to configure, monitor, and troubleshoot the system with ease. Whether used for discrete signal processing, analog measurement, or digital communication, this terminal block delivers consistent performance and operational stability, making it a trusted component in Siemens automation ecosystem.

For applications requiring **high-speed data transmission or deterministic communication**, the **6ES5751-3AA12** can be paired with Siemens **PROFIBUS DP, PROFINET, or other industrial communication protocols**, further enhancing its versatility. Its robust construction and adherence to **IEC/EN standards** ensure compliance with international safety and performance regulations, while its **low power consumption** contributes to energy-efficient operation. Whether deployed in a factory automation setting, a building automation system, or a process control environment, this terminal block exemplifies Siemens commitment to delivering **high-quality, future-proof solutions** that enhance productivity and operational efficiency.

### **Analysis of Siemens 6ES5751-3AA12 (S7-300 CPU 315-2DP) Pros and Cons**

#### **Overview**

The **Siemens 6ES5751-3AA12** is a **CPU 315-2DP** module from the **S7-300** series, commonly used in industrial automation for PLC (Programmable Logic Controller) applications. It features **2 digital inputs, 2 digital outputs, and 2 analog inputs (0 20 mA or 4 20 mA)** with a **16 MB data memory** and support for **PROFIBUS DP** communication.

---

### **Pros**

1. **Reliability and Proven Track Record**

- Part of Siemens **S7-300** series, which has been widely used in industrial environments for decades. The CPU 315-2DP is a well-established model with a strong reputation for durability.

- Siemens is a **global leader in industrial automation**, ensuring consistent hardware and software support.

2. **Cost-Effective for Small to Medium Control Tasks**

- More affordable than higher-end S7-400 or S7-1200/1500 CPUs, making it suitable for **budget-conscious projects** where advanced features are unnecessary.

- Lower initial cost compared to newer S7-1200/1500 CPUs with similar I/O capabilities.

3. **Sufficient I/O for Basic Automation**

- The **2 digital inputs, 2 digital outputs, and 2 analog inputs** are adequate for **simple control applications**, such as:

- Basic motor control (start/stop, direction)

- Temperature/pressure monitoring (via analog inputs)

- Discrete sensor/actuator management

- Expandable via **S7-300 I/O modules** (e.g., 6ES7391-1BG20-0XB0 for additional digital I/O).

4. **PROFIBUS DP Support**

- Compatible with **PROFIBUS DP**, a **fieldbus standard** widely used in industrial networks, allowing integration with other Siemens devices (e.g., HMIs, drives, sensors).

- Useful in **distributed control systems** where multiple devices communicate over a single bus.

5. **Backward Compatibility and Legacy Support**

- Works with **Siemens TIA Portal (V13 )** and **STEP 7 (V5.5 )** software, ensuring long-term compatibility.

- Still supported by Siemens in **maintenance and spare parts**, though newer replacements (e.g., S7-1200) may be preferred for future projects.

6. **Modular and Extensible**

- Can be paired with **additional I/O modules** (e.g., 6ES7391-xxx series) to expand functionality without replacing the CPU.

- Supports **remote I/O** via PROFIBUS, useful for distributed control setups.

7. **Energy Efficiency**

- Lower power consumption compared to some newer CPUs, reducing operational costs in long-running applications.

---

### **Cons**

1. **Limited I/O Capacity for Complex Systems**

- The **2 analog inputs and 2 digital I/O** are restrictive for **large-scale or high-density automation tasks**.

- Requires **additional modules** (e.g., 6ES7391-1KD20-0XB0 for more analog inputs) to meet advanced needs, increasing system complexity.

2. **Outdated Compared to Modern Alternatives**

- **S7-1200/1500 CPUs** (e.g., 6ES7151-1BF30-0XB0) offer:

- **More I/O channels** (integrated or via expansion modules).

- **Higher processing power** (better for real-time tasks).

- **Ethernet/Profinet support** (modern industrial networking).

- **Simpler programming** (TIA Portal is more intuitive than STEP 7 for newer users).

- The **S7-300 series is nearing end-of-life**, with Siemens shifting focus to **S7-1200/1500 and S7-1500**.

3. **Software Limitations**

- **STEP 7 (V5.5)** is **less user-friendly** than **TIA Portal**, which has a more modern interface.

- **No built-in Ethernet/Profinet** (requires additional modules like 6ES7391-7KF00-0XB0 for Ethernet).

- **Limited support for advanced features** (e.g., motion control, advanced diagnostics) compared to newer S7 models.

4. **Higher Maintenance and Spare Parts Costs Over Time**

- As Siemens **phases out S7-300**, **spare parts and technical support** may become harder to obtain in the long term.

- **Newer CPUs (S7-1200/1500) are more cost-effective** for new installations due to lower long-term support costs.

5. **Physical Size and Installation Constraints**

- The **S7-300 rack-mount design** requires **1 EU space**, which may be less flexible than **compact S7-1200/1500 CPUs** that can be mounted on DIN rails or in enclosures.

- **PROFIBUS dependency** means additional wiring and infrastructure if not already present.

6. **No Built-in Safety Functions**

- Unlike newer S7-1200/1500 models, the **CPU 315-2DP does not support integrated safety (e.g., S7-1200 with Safety Integrated)**.

- Requires **external safety relays or PLCs** for safety-critical applications, increasing system complexity.

7. **Limited Expansion Options**

- **No integrated Ethernet or Profinet** means extra modules are needed for modern networking.

- **Analog inputs are limited to 2 channels**, requiring additional modules for more signals.

---

### **Conclusion**

The **Siemens 6ES5751-3AA12 (CPU 315-2DP)** is a **solid, reliable choice for simple automation tasks** where **cost, legacy compatibility, and basic I/O requirements** are prioritized. It remains a **practical option for retrofitting or maintaining existing S7-300 systems**, especially in industries where **PROFIBUS is already in use**.

However, for **new projects**, the **S7-1200 or S7-1500 series** offers **superior performance, modern networking, and easier programming**, making them the **preferred long-term investment**. The **CPU 315-2DP is best suited for:**

- **Small-scale control applications** (e.g., basic machine control, sensor monitoring).

- **Systems where PROFIBUS is already implemented**.

- **Budget-conscious upgrades** where replacing the entire system is not feasible.

If you **must use this CPU**, ensure you have:

**Backup power supply** (S7-300 CPUs can be sensitive to power fluctuations).

**Spare modules** (I/O, power supplies) for future expansion.

**Documented STEP 7 projects** (for easy migration if needed).

For **new installations**, consider upgrading to an **S7-1200 or S7-1500 CPU** for **better scalability, networking, and future-proofing**.

---

### **Final Recommendation**

- **Buy the 6ES5751-3AA12 if:**

- You are **maintaining an existing S7-300 system**.

- Your application requires **only basic I/O and PROFIBUS communication**.

- Cost is a **primary concern**, and you do not need advanced features.

- **Avoid buying new for a fresh project unless:**

- You have **specific compatibility requirements** with legacy S7-300 devices.

- The **total cost of ownership (TCO) is justified** by your current infrastructure.

- **For new projects, consider:**

- **S7-1200 CPU (e.g., 6ES7121-1BG20-0XB0)** Compact, Ethernet/Profinet, easier programming.

- **S7-1500 CPU (e.g., 6ES7151-1BF30-0XB0)** Higher performance, integrated safety, future-proof.

The **6ES5751-3AA12 is a functional but outdated solution** best suited for **legacy systems rather than new automation builds**.

Details:

Sells new and surplus product develops channels to purchase such. All products are guaranteed to be working but may show signs of use if purchasing a used product. Call to use a shipping service other than the ones listed. Packaging and Handling: Items are safely ESD packaged in custom shipping cartons for protection.

part #: 6es57513aa12 prices

  • $295.00-$360.00

specifications sensoindustria:

  • brand: Siemens
  • mpn: 6es5751-3aa12
  • part type: Module

general sensoindustria:

  • condition: Used
  • PLCs HMIs > PLC Peripheral Modules > PLC Input Output Modules

seller sensoindustria:

  • # reviews: 192778
  • rating: 99.6%
  • city: 1 Millennium Dr, Willingboro, NJ 08046

payments sensoindustria:

  • credit card: Diners-club
  • wallet: Google-pay
  • other

offer sensoindustria:

  • sold: 0
  • availability: In Stock
  • started: March 3, 2026
  • quantity: 1
  • options: Ship-to-home

returns sensoindustria:

  • paid by: Buyer
  • policy: Returns Accepted
  • time: 30 Days
  • method: Money back

shipping sensoindustria:

  • cost: $12.90
  • type: Fixed
  • service: Standard
  • class: Standard
  • transit: 29-34 Days
part type: module,
category: business & industrial > plcs hmis > plc peripheral modules > plc input output modules, sku: 21159341970059713,
Siemens 6ES5751-3AA12 Is Similar To:
sensoindustria logo
2 offers $295.00–$360.00 USD
  • Used. Offer #1 priced at $295.00 + $31.00 shipping estimate = $326.00* total. The unit is in great working condition !.+$31.00 shipping
  • Used. Offer #2 priced at $360.00 + $12.90 shipping estimate = $372.90* total. FACTORY WARRANTY MAY NOT APPLY.+$12.90 shipping

Copyright © sensoindustria.com