Square D HJA36040 - 40A, 3-Pole, Circuit Breaker

Meet the Square D HJA36040 40A, 3-Pole Circuit Breaker — a purpose-built solution for reliable, fail-safe protection in demanding electrical environments. Built to shield your critical equipment from overcurrent, this breaker delivers consistent performance in the most active distribution setups.

Designed for industrial, commercial, and OEM applications, this 3-pole breaker is ideal for panelboards, switchboards, and control panels where dependable protection and safe operation are non-negotiable. Its 40-amp rating provides a precise balance between protecting wiring and enabling smooth startup of connected loads.

• Current rating: 40A
• Poles: 3-Pole
• Breaker type: Circuit Breaker
• Applications: Suitable for panelboards, switchboards, control panels, distribution panels, and motor control centers

What makes this Square D device stand out is its three-phase configuration, which ensures uniform protection across all conductors in a 3-phase system. In motor control centers and other multi-phase applications, a single 3-pole breaker simplifies wiring, aligns with standard three-phase loads, and helps maintain balanced protection. This translates to reduced risk of phase imbalances, minimized downtime after faults, and easier maintenance planning.

Use cases you’ll encounter in the field include protecting three-phase motors, conveyors, pumps, fans, HVAC units, and other industrial equipment. In commercial settings, it can safeguard machinery in processing lines and automated systems. For OEMs, the HJA36040 provides a reliable, drop-in option that aligns with Square D panel designs and MCC configurations, helping you deliver safer, compliant machines faster.

Installation and operation are straightforward: select a 3-pole, 40A circuit breaker compatible with your Square D panel infrastructure, ensure proper panel allocation for three-phase protection, and apply standard commissioning practices to verify correct tripping and restoration behavior. When a fault occurs, you’ll enjoy clear isolation of the affected circuit, protecting both wiring and equipment from damage.

Choose the Square D HJA36040 for robust, field-proven overcurrent protection that keeps critical systems online and performing at their best. It’s a practical, reliable choice for professionals who demand consistency, safety, and easy integration across panelboards, switchboards, and control panels in demanding environments.