Square D HDL36150U31X - 150 A, 3-Pole Circuit Breaker | AmpState

Square D HDL36150U31X is a 150 A, 3-pole molded case circuit breaker designed to shield panelboards and load centers from overcurrent and short circuits. Built for durability, its compact molded-case design optimizes panel space without compromising protection.

The thermal-magnetic trip unit delivers stable, repeatable protection by combining a thermal element for overload and a magnetic element for short-circuit events. This means predictable tripping behavior across varying temperatures and load conditions, helping prevent nuisance trips and equipment damage.

Key advantages

• Space-efficient molded case fits neatly in residential, commercial, and light industrial panels, freeing up interior space for wiring and future expansion.
• Three-pole configuration suitable for 3-phase distribution, ideal for small commercial panelboards and load centers.
• 150 A, robust protection guards branch circuits against overcurrent and short circuits, reducing downtime and equipment wear.
• OEM compatibility designed to work with matching Square D OEM load centers and panelboards for reliable, plug-and-play installation.
• Versatile applications suitable for residential, commercial, and light industrial environments, including lighting, motors, and general electrical equipment.

Technical specifications at a glance

• Manufacturer: Square D
• Part Number: HDL36150U31X
• Type: Thermal-magnetic molded case circuit breaker
• Amperage rating: 150 A
• Poles: 3
• Application: Branch circuit overcurrent and short-circuit protection

Who should consider this breaker?

Electrical professionals and facility managers working with Square D panels will appreciate the built-in reliability of the HDL36150U31X. If you’re upgrading an aging panel, expanding a 3-phase system, or replacing a failed breaker in a residential, commercial, or light industrial setting, this 3-pole 150 A unit offers a straightforward, code-compliant solution for continuous operation and protection.

Practical tips

• Confirm the replacement breaker is compatible with your specific Square D panelboard or load center model for a seamless fit.
• Use the thermal-magnetic trip as intended: overloads get dissipated by the thermal element while short circuits trigger the magnetic mechanism for a fast interruption.
• Schedule periodic inspection of panel interiors to ensure connections remain tight and insulation is intact, reducing the risk of overheating.