Square D HJA36020 - 20 A, 600 V, 3-Pole Plug-In Circuit Breaker | AmpState

The Square D HJA36020 is a robust 3-pole, 20A, 600V plug-in molded case circuit breaker designed to protect branch circuits in panelboards and load centers. Its fast plug-in connection means quick installation and simple future replacements, keeping downtime to a minimum in active electrical environments.

At the heart of the unit is a thermal-magnetic trip system that delivers stable, repeatable protection. The thermal element handles gradual overloads with predictable timing, while the magnetic element provides instantaneous interruption during short-circuit events, shielding wiring, devices, and surrounding equipment from damage.

This breaker is built to match OEM Square D load centers and panelboards, ensuring a seamless, code-compliant fit within your existing enclosure. Its plug-in design simplifies maintenance and upgrades, reducing field wiring complexity and improving serviceability during panel work.

Ideal for residential, commercial, and light industrial applications, the HJA36020 is well-suited for service upgrades, retrofit projects, and new installations where reliable overcurrent and short-circuit protection is essential.

Technical specifications

• Manufacturer: Square D
• Part number: HJA36020
• Type: Thermal-magnetic molded case circuit breaker
• Amperage rating: 20 A
• Voltage rating: 600 V
• Number of poles: 3
• Mounting style: Plug-in
• Application: Branch circuit overcurrent and short-circuit protection

Use scenarios

• Upgrading protection in small to mid-size panelboards where fast plug-in replacement minimizes equipment downtime
• Retrofits and service upgrades in existing Square D installations to maintain consistent protection profiles
• Protecting individual branch circuits in residential systems and light commercial setups
• Configurations requiring a 600 V maximum rating with reliable 3-pole protection

For reliable, code-compliant protection with straightforward installation, the Square D HJA36020 delivers precise, predictable performance when it matters most—in both new builds and upgrades across a range of commercial and industrial environments.