Square D D321NRB - 30A, 240V, 3-Pole, Fused Disconnect Switch

The Square D D321NRB fused disconnect switch is engineered for demanding industrial and commercial environments where safe electrical isolation is non-negotiable. With a 30A, 240V, 3-pole configuration, this unit delivers dependable, three-phase disconnection when maintenance or servicing is required, helping protect personnel and equipment alike.

• Three-pole isolation guarantees all live lines disconnect together, minimizing arcing risk and streamlining interlock sequences in complex switchgear.
• Integrated fusing provides immediate overcurrent protection at the disconnect point, reducing the chance of damage to downstream equipment.
• NEMA 3R enclosure offers rugged, weather-resistant protection suitable for outdoor installations and harsh environments without compromising safety or performance.
• Lockout/Tagout readiness supports compliant, visible safety practices, making maintenance procedures clearer and safer for teams.
• Durable, field-ready design is built to withstand frequent operation and long service life in demanding settings.

Why this design matters in real-world use

• It provides a reliable isolation point for large motors, pumps, conveyors, and HVAC equipment, enabling safe servicing and maintenance with confidence.
• By combining disconnection with overcurrent protection in a single unit, it simplifies wiring and reduces the footprint in control panels.
• The weather-resistant enclosure maintains consistent performance whether installed indoors, on loading docks, or in outdoor equipment housings.

Ideal use cases

• Factories and warehouses with 3-phase motors and machinery that require regular maintenance.
• Outdoor equipment housings, pumping stations, and outdoor HVAC installations needing a rugged disconnect solution.
• Maintenance planning for production lines where a clear, safe, and compliant isolation point is essential.

Specification highlights

• Brand: Square D
• Model: D321NRB
• Product Type: Fused Disconnect Switch
• Amperage Rating: 30A
• Voltage Rating: 240V
• Number of Poles: 3-Pole
• Enclosure Rating: NEMA 3R

In short, the Square D D321NRB fused disconnect switch offers precise, safe, and durable electrical isolation for three-phase systems, backed by a robust enclosure and lockout-ready design that keep maintenance crews protected and productivity on track.