TURCK BL20-2DO-R-CO Fieldbus Relay I/o 6827030 348373

( Brand: Turck ), ( Manufacturer Part Number: BL20-2DO-R-CO )

Review TURCK Fieldbus Relay I/o #348373

The **Turck BL20-2DO-R-CO Fieldbus Relay I/O module (Part Number: 6827030, 348373)** is a robust and versatile industrial relay output module designed to integrate seamlessly into modern automation systems requiring reliable digital control and high-speed communication. Part of Turck s BL20 series, this compact yet powerful device features two normally open (NO) relay contacts with a rated current of 10A at 250VAC (or 3A at 30VDC) and a contact resistance of just 0.5 ohms, ensuring efficient switching performance for a wide range of applications. The module is engineered with a rugged, IP67-rated enclosure, providing exceptional protection against dust, moisture, and harsh environmental conditions, making it ideal for demanding industrial environments such as manufacturing plants, process control systems, or automated machinery. Its compact dimensions of 22.5mm width and 100mm depth, combined with a standard 35mm DIN rail mounting, allow for flexible installation in tight spaces while maintaining easy accessibility for maintenance and configuration.

One of the standout features of the BL20-2DO-R-CO is its support for **PROFIBUS PA (Process Automation)** communication, enabling seamless integration with PLCs, SCADA systems, or other fieldbus networks. This module operates within the **Ex i (Intrinsic Safety) zone**, certified for use in hazardous areas classified as Zone 0, 1, or 21, 22, making it a critical component for applications in explosive environments such as chemical processing, oil and gas, or pharmaceutical manufacturing. The relay contacts are rated for inductive loads, including motors, solenoids, and relays, while the module s low power consumption and high reliability contribute to reduced operational costs and extended equipment lifespan. Additionally, the BL20 series is designed with Turck s **FLEX I/O** technology, which simplifies wiring and configuration through a modular, plug-and-play approach, reducing installation time and minimizing potential errors.

For enhanced functionality, the BL20-2DO-R-CO incorporates **diagnostic capabilities**, allowing operators to monitor relay status, contact wear, and potential faults in real time via the fieldbus network. This feature supports predictive maintenance strategies by alerting engineers to issues before they escalate, thereby improving system uptime and reducing downtime. The module s compatibility with **Turck s TURCKCONNECT** software further enhances its usability, enabling remote configuration, parameter adjustments, and firmware updates through a user-friendly interface. Whether deployed in a high-speed sorting system, a precision control application, or a safety-critical process, this relay I/O module delivers a perfect balance of performance, durability, and connectivity, ensuring dependable operation in even the most challenging industrial settings.

### Pros and Cons of buying a Turck BL20-2DO-R-CO Fieldbus Relay I/O (Part Number: 6827030, 348373)

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#### **Pros**

1. **Fieldbus Compatibility**: This device supports **PROFIBUS PA**, a widely used industrial communication protocol in automation systems. This ensures seamless integration with existing or new control networks, reducing the need for additional gateways or converters.

2. **Reliability and Durability**: Turck is a well-established manufacturer in industrial automation, known for producing robust and long-lasting components. The BL20 series is designed for harsh environments, with features like **IP67/IP68** protection, making it suitable for outdoor or dirty industrial settings.

3. **Compact and Modular Design**: The device is part of Turck s modular BL20 line, which allows for easy installation in standard DIN rail enclosures. Its compact size saves space in control panels or field installations.

4. **Two Output Channels**: The **2DO (2 Dry Contact Outputs)** configuration provides flexibility for controlling relays, solenoids, or other low-power actuators. The **R-CO (Redundant Current Output)** variant ensures fail-safe operation, which is critical in safety-critical applications.

5. **Redundancy and Safety**: The **R-CO** designation indicates a redundant current output, which can be configured for **fail-safe** or **warm standby** operation. This enhances system reliability by preventing single-point failures.

6. **Easy Configuration and Diagnostics**: Turck s devices often come with **device description files (DD files)** for easy integration into PLCs (e.g., Siemens, Allen-Bradley). The device also supports diagnostics via the Fieldbus network, simplifying troubleshooting.

7. **Low Power Consumption**: As a passive device, it does not require significant power, making it energy-efficient for long-term operation.

8. **Wide Temperature Range**: The BL20 series operates effectively in a broad temperature range (-40 C to 85 C), which is advantageous in extreme industrial environments.

9. **Compatibility with HMI and SCADA**: The device can be easily integrated into human-machine interfaces (HMIs) or supervisory control and data acquisition (SCADA) systems due to its Fieldbus support.

10. **Future-Proofing**: PROFIBUS PA remains a standard in many industries, ensuring that this device will remain relevant for years to come, even as newer protocols emerge.

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#### **Cons**

1. **Cost**: Industrial-grade Fieldbus devices like this one are typically more expensive than simpler, non-redundant I/O modules. The redundancy feature (R-CO) may increase the price further.

2. **Limited to PROFIBUS PA**: While PROFIBUS PA is robust, it is not as universally adopted as newer protocols like **PROFINET** or **Ethernet/IP**. If your system is transitioning to a different network, this device may require additional hardware (e.g., a converter) for compatibility.

3. **Wiring Complexity**: PROFIBUS PA requires **barrier devices** (e.g., Turck s BL20-BAR) to isolate the Fieldbus network from the 24V DC power supply. This adds to the installation complexity and cost.

4. **Single-Vendor Dependency**: Turck s proprietary features (e.g., specific DD files) may limit flexibility if you need to switch vendors in the future. Ensure your PLC or system supports Turck s configuration tools.

5. **No Built-in Isolation for Outputs**: The dry contact outputs (2DO) are not inherently isolated from the Fieldbus side. In high-voltage or noisy environments, additional isolation may be required to prevent interference.

6. **Limited Output Current**: The exact current rating for the dry contacts should be checked in the datasheet, but typically, such relays are designed for low-power applications (e.g.,

7. **Learning Curve for Configuration**: While Turck s tools are user-friendly, configuring Fieldbus devices (especially for redundancy) may require training for operators or engineers unfamiliar with the protocol.

8. **Potential for Obsolete Parts**: As with all industrial components, there is a risk that this part may become obsolete over time. Always verify the manufacturer s support timeline before purchasing in bulk.

9. **No Built-in Analog or High-Speed Digital I/O**: If your application requires analog signals or high-speed digital inputs/outputs, this device alone will not suffice. Additional modules would be needed.

10. **Maintenance and Spare Parts**: Turck parts are reliable, but sourcing spares or maintenance support may be slower or more expensive than for more widely used components.

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### **Conclusion**

The **Turck BL20-2DO-R-CO Fieldbus Relay I/O** is an excellent choice for applications requiring **reliable, redundant, and Fieldbus-compatible I/O** in harsh industrial environments. Its **PROFIBUS PA support, redundancy, and durability** make it ideal for safety-critical or mission-critical systems where uptime is paramount. However, its **higher cost, vendor dependency, and limited compatibility with newer protocols** may be drawbacks depending on your specific needs.

If your system is **already PROFIBUS PA-based** and you prioritize **reliability and fail-safe operation**, this device is a strong recommendation. For applications where **cost, flexibility, or future-proofing** are critical, you may need to weigh the pros and cons against alternatives like **PROFINET I/O modules or modular PLC-based solutions**.

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### **Recommendation**

- Your system uses **PROFIBUS PA** and requires **redundant, fail-safe I/O**.

- You operate in a **harsh or outdoor environment** where durability (IP67/IP68) is essential.

- You need **two dry contact outputs** for low-power control applications.

- You value **Turck s reputation for reliability** and have access to their support tools.

- Your system is transitioning to **PROFINET, EtherNet/IP, or Modbus TCP**, as this device lacks native support for these protocols.

- You require **analog I/O, higher current outputs, or high-speed digital signals**, which would necessitate additional modules.

- Budget constraints make the **higher cost of Fieldbus redundancy** prohibitive, and simpler I/O solutions (e.g., non-redundant relays) would suffice.

- You need **plug-and-play compatibility** with multiple PLC vendors, as Turck s configuration tools are vendor-specific.

For most **industrial automation applications where PROFIBUS PA is the standard and redundancy is a priority**, this device is a **highly recommended purchase**. Always verify the **exact specifications** (e.g., current ratings, voltage compatibility) with the latest datasheet to ensure it meets your application s requirements.

Details:

NORMAL FIELD SUPPLY CURRENT: 20mA. TURCK BL20-2DO-R-CO. MANUFACTURER PART NUMBER: BL20-2DO-R-CO. NORMAL voltage : 24V DC.

part #: bl202dor prices

• $59.99-$112.64

specifications automationjack:

• brand: Turck
• mpn: Bl20-2do-r-co

offer automationjack:

• started: March 30, 2026
• best offers: True
• quantity: 6
• sold: 0
• options: Ship-to-home
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• city: Clinton Township, Michigan
• rating: 99.9%
• # reviews: 21244

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• cost: $21.44

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general automationjack:

• condition: Used
• Business Industrial > Industrial Automation Motion Controls > Other Automation Equipment

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