Square D HDA36125UD 125A 3-Pole 600 V Circuit Breaker

Meet the Square D HDA36125UD 125A 3-Pole 600 V circuit breaker—a compact, dependable protection device designed for 3‑phase electrical systems in commercial and light‑industrial environments. This unit is built to safely interrupt faults and protect feeders and motors in circuits up to 125 amperes operating at 600 volts, making it a practical choice for mid‑sized distribution needs.

Key specifications

• Current rating: 125 A
• Pole configuration: 3-pole
• Maximum voltage: 600 V
• Part number: HDA36125UD
• Brand: Square D

Ideal applications

Use this 3‑pole breaker to guard 3‑phase feeders powering motors, conveyors, and distribution circuits in manufacturing spaces, mechanical rooms, data centers, and commercial electrical rooms. Its 125 A protection level is well-suited for mid‑size loads in 600 V systems, helping to limit damage from overloads and short circuits while minimizing downtime.

What sets it apart

• Direct fit for compatible Square D panels: Simplifies replacement or initial installation with a proven form factor.
• Three‑phase protection: Ensures coordinated interruption across all phases for balanced, reliable circuit shutdowns.
• 125 A rating for common feeders: Provides precise protection without oversizing, supporting efficient electrical design.

Practical tips for installation and care

• Verify panel compatibility by checking your Square D panel labeling and cross‑reference against the HDA series.
• During installation, ensure secure mounting and proper conductor sizing for 125 A circuits to maintain consistent protection.
• Use the exact part number HDA36125UD to preserve electrical protection integrity and compatibility with your existing Square D system.