Siemens 3RT7926-1CB00 AC/DC Surge Suppressor Protector

The Siemens 3RT7926-1CB00 AC/DC Surge Suppressor Protector is engineered to safeguard sensitive electrical equipment from transient overvoltages, ensuring operational reliability and longevity in demanding industrial environments. This compact yet robust device offers superior protection against lightning strikes and switching surges, making it an indispensable component for critical infrastructure. Its key advantages include broad applicability across AC and DC systems, a high surge current rating, and seamless integration capabilities. Core features encompass advanced suppression technology, a durable design for harsh conditions, and clear status indication. Important technical parameters include an operating voltage range of 24-230V AC/DC and a maximum continuous operating voltage of 280V AC/DC, with a nominal discharge current (In) of 10kA and a maximum discharge current (Imax) of 20kA.

Product Specifications

| Feature                        | Specification                               |

| :----------------------------- | :------------------------------------------ |

| Product Type                   | AC/DC Surge Suppressor Protector            |

| Manufacturer                   | Siemens                                     |

| Model Number                   | 3RT7926-1CB00                               |

| Operating Voltage              | 24-230 V AC/DC                              |

| Max. Continuous Operating Voltage | 280 V AC/DC                                 |

| Nominal Discharge Current (In) | 10 kA                                       |

| Maximum Discharge Current (Imax) | 20 kA                                       |

| Protection Level (Up)          | ≤ 1.5 kV                                    |

| Response Time                  | < 25 ns                                     |

| Operating Temperature Range    | -40°C to +80°C                              |

| Protection Class               | IP20 (housing)                              |

| Mounting                       | DIN rail (35 mm)                            |

| Dimensions (W x H x D)         | 17.5 mm x 90 mm x 63 mm                     |

| Certifications                 | CE, UL, CSA                                 |

Core Features & Market Positioning

The Siemens 3RT7926-1CB00 stands out in the industrial surge protection market due to its dual AC/DC capability, offering a versatile solution for a wide array of applications where mixed voltage systems are common. This eliminates the need for separate protective devices for AC and DC circuits, simplifying inventory and installation. Its high surge current handling capacity of 20 kA ensures robust protection against severe transient events, a critical factor in maintaining the uptime of expensive control systems, drives, and automation equipment. Market positioning is further solidified by Siemens' reputation for reliability and advanced engineering, providing users with confidence in the product's performance and longevity. The device's compact 17.5mm width allows for space-saving installation within control cabinets, a significant advantage in densely populated panels.

Key Application Scenarios

This surge suppressor is ideally suited for protecting control circuits, power supplies, and automation systems in various industrial sectors. Its application in manufacturing plants ensures the integrity of Programmable Logic Controllers (PLCs), Human-Machine Interfaces (HMIs), and variable frequency drives (VFDs) against damaging voltage spikes, thereby minimizing production downtime. In building automation, it safeguards HVAC systems, lighting controls, and security equipment from surges originating from the grid or internal switching operations. Furthermore, its robust design makes it suitable for renewable energy installations, protecting inverters and control systems in solar and wind power applications, where transient events can be frequent and severe.

Practical System Integration Guidance

Integrating the Siemens 3RT7926-1CB00 into existing electrical systems is straightforward due to its standard DIN rail mounting and clear terminal markings. For optimal performance, it should be installed as close as possible to the equipment it is protecting, typically at the input terminals of the protected device or the main distribution board. Wiring should adhere to local electrical codes and standards. The device connects in parallel with the power supply lines. For AC systems, connect Line and Neutral to the input terminals; for DC systems, connect the positive and negative terminals accordingly. A dedicated protective earth connection must be made to the grounding terminal to ensure effective dissipation of surge energy. The response time of less than 25 ns ensures rapid intervention during a transient event.

Operation and Risk Mitigation

The Siemens 3RT7926-1CB00 operates passively, requiring no external power supply. Its advanced metal oxide varistor (MOV) technology effectively diverts excess voltage to ground while allowing normal operation to continue unimpeded. Visual status indicators, if integrated into the specific variant or associated signaling modules, provide immediate feedback on the protector's operational status, though this specific model primarily relies on its inherent functionality. Risk mitigation is achieved through its high surge current rating and robust construction, designed to withstand multiple surge events. While the device is highly reliable, regular inspection of connections and the surrounding electrical environment is recommended to ensure sustained protection and prevent potential hazards associated with equipment malfunction.

Scalability & Long-Term Value

The Siemens 3RT7926-1CB00 offers significant long-term value by enhancing the reliability and extending the operational life of connected equipment, thereby reducing maintenance costs and the risk of costly downtime. Its compatibility with a wide range of Siemens automation components and other standard industrial electrical systems ensures flexibility in system design and upgrades. While this specific model is a fixed-function device, it can be part of a layered surge protection strategy. Integrating it alongside upstream and downstream protection devices creates a comprehensive defense system. For industries moving towards digital transformation and the Industrial Internet of Things (IIoT), robust and reliable power infrastructure, underpinned by effective surge protection, is foundational for the continuous operation of connected devices and data acquisition systems.

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Frequently Asked Questions (FAQs)

1. What is the primary function of the Siemens 3RT7926-1CB00?

The primary function is to protect electrical equipment from damaging voltage spikes and surges.

It acts as a sacrificial component, diverting excess energy to ground.

This safeguards sensitive electronics, ensuring operational continuity and reducing failure rates.

2. Can the 3RT7926-1CB00 be used for both AC and DC circuits?

Yes, it is specifically designed for dual AC/DC applications.

This versatility allows it to protect a broad range of industrial power systems.

It simplifies installation and inventory by serving multiple circuit types.

3. What is the maximum surge current this protector can handle?

It can handle a maximum discharge current (Imax) of 20 kA.

This high rating ensures protection against significant transient events like lightning strikes.

It provides a robust defense for critical control and automation systems.

4. How is the 3RT7926-1CB00 installed in an electrical panel?

It mounts directly onto a standard 35 mm DIN rail.

Installation should be as close as possible to the equipment being protected.

Proper grounding connection is essential for effective surge dissipation.

5. What is the operating voltage range for this surge suppressor?

The device operates with voltages ranging from 24 to 230V AC or DC.

Its maximum continuous operating voltage is 280V AC/DC.

This wide range covers most common industrial power supply requirements.

6. Does the 3RT7926-1CB00 require a separate power source to function?

No, it operates passively and requires no external power.

Its protection mechanism is self-contained within the device.

This ensures reliable protection even during power fluctuations.

7. What is the response time of the Siemens 3RT7926-1CB00?

The response time is very fast, occurring in less than 25 nanoseconds.

This rapid reaction is crucial for intercepting transient surges before they reach sensitive components.

It minimizes the potential for damage during short-duration voltage spikes.

8. What are the typical applications for this surge protector?

Common applications include protecting PLCs, VFDs, and HMIs in industrial automation.

It is also used for power supplies, control circuits, and in building automation systems.

Renewable energy systems also benefit from its protection capabilities.

9. How can I determine if the 3RT7926-1CB00 is functioning correctly?

This model typically does not have a visual indicator of its own status.

Functionality is confirmed through proper installation and the absence of equipment failure.

Periodic system checks and monitoring of protected equipment are recommended.

10. Is this surge protector compatible with other Siemens automation components?

Yes, it is designed to integrate seamlessly with Siemens' extensive range of automation products.

Its standard specifications ensure compatibility with most industrial electrical systems.

This facilitates its inclusion in both new designs and upgrade projects.