3VA9378-0LB10 - Handle Blocking Device - 3VA 250-600A

3VA9378-0LB10 -  Handle Blocking Device - 3VA 250-600A

Unlock confidence in your electrical control setup with the Siemens 3VA9378-0LB10 Lock-Off Accessory. Designed to enhance safety and compliance, this accessory gives you a dependable way to lock breakers into the off position — preventing accidental re-energization during maintenance or emergency work. Whether you’re a professional electrician, facility manager, or DIY enthusiast, this lock-off provides peace of mind without complicating your workflow. Crafted by Siemens, a leader in industrial and commercial electrical components, the 3VA9378-0LB10 lock-off integrates smoothly with compatible breakers and panels. Its compact form factor and straightforward design make installation quick, and its quality construction provides longer useful life in demanding environments. If safety and ease of use matter to you, this lock-off is a smart addition to your electrical safety strategy.

Key Features and Benefits

• Enhanced Safety: Keeps breakers secured in the OFF position to protect workers and equipment during service or repair.
• User-Friendly Design: Simple to install and remove without specialized tools; easy for technicians to work with on the job.
• Compact and Practical: Small footprint (3.0″ H × 3.0″ W × 0.5″ D) fits into tight panel spaces without interfering with adjacent components.
• Trusted Brand Quality: Backed by Siemens’ reputation for consistent performance and dependable electrical accessories.
  

Technical Specifications

• Part Number: 3VA9378-0LB10
  
• Vendor: Siemens
  
• Type: Lock-Off Accessory
  
• Height: 3.0 inches
  
• Width: 3.0 inches
  
• Depth: 0.5 inches
  
• Poles: N/A (Accessory)
  
• Amperes / A.I.C. Rating & Volts: N/A (Accessory works with compatible breakers)
  

Note: This product is an accessory designed to secure compatible circuit breakers. It does not carry current on its own.

Material Compliance and Certifications

• Industry Standards: The Siemens 3VA9378-0LB10 meets industry standards for electrical safety accessories and aligns with regulatory expectations where lock-off devices are required.
• Manufacturing Quality: Manufactured to quality guidelines that ensure consistent performance, this accessory supports safe electrical practices across industrial, commercial, and institutional applications.
  

Where It Works Best

• Maintenance and Service Areas – Prevents unplanned energizing while technicians are working.
• Industrial Facilities – Adds a layer of personnel protection in manufacturing and processing plants.
• Commercial Electrical Rooms – Helps facilities managers enforce lock-out/tag-out procedures.
• Educational and Healthcare Settings – Enhances operational safety and compliance with workplace safety protocols.