Square D D321NRB - 30A, 240V, Fused Disconnect Switch

Square D D321NRB is a 30A, 240V fused disconnect switch designed to deliver safe, reliable electrical isolation in demanding industrial and commercial environments. This unit combines the essential isolation function with integrated fuse protection, providing a compact, dependable solution for shutting down equipment while guarding against short circuits and overloads.

Why this matters

• Integrated protection and isolation — The fused disconnect switch performs both disconnection and overcurrent protection in a single device, helping simplify electrical panels and reduce the number of components you manage.
• Lockout/Tagout compatibility — Built to support proper lockout/tagout procedures, helping your team maintain safety standards during maintenance and servicing.
• Industrial reliability — Engineered for long-term durability in harsh environments, delivering consistent performance for routine shutdowns, test procedures, and emergency isolation.
• Clear suitability for 240V circuits — Ideal for a wide range of 240V applications in control panels, equipment rooms, and service disconnects where dependable operation is critical.

Ideal use cases

• Control panels and motor control centers requiring a trustworthy disconnect with built-in fuse protection.
• Equipment service points where safe isolation must be verified before maintenance or repair work.
• Mid-sized industrial circuits in manufacturing, processing, and packaging environments that demand quick, safe shutdowns.

What makes it stand out

The D321NRB offers a streamlined approach to electrical safety by combining a clear disconnect function with protective fusing, reducing the risk of accidental energization during service and improving overall maintenance workflow. Its rugged design supports continuous operation in facilities where uptime and safety are non-negotiable.

Practical guidance for maximum value

• Pair with standard safety practices and lockout/tagout procedures to ensure compliant, safe maintenance work.
• Use in circuits where 30A current and 240V operation are within the design requirements to protect equipment and personnel.
• Maintain fuses according to facility guidelines, replacing only with the same ratings to preserve protective performance.