Square D EJB34125 - 125 A, 480 V, 3-Pole Bolt-On Circuit Breaker | AmpState

The Square D EJB34125 is a rugged 125 A, 480 V, 3-pole bolt-on molded case circuit breaker designed to protect your panelboards and loadcenters with reliable, predictable performance. Built for demanding commercial and light industrial environments, this unit delivers dependable branch circuit overcurrent and short-circuit protection where it matters most.

• Secure bolt-on mounting provides a rigid, vibration-resistant bus connection, reducing wear and ensuring consistent electrical contact in busy electrical rooms and equipment closets.
• Thermal-magnetic trip unit combines thermal overload protection with magnetic short-circuit protection for fast, stable responses and repeatable protection curves across varying temperatures and loads.
• 3-pole, 480 V design is ideal for three-phase power distribution, safeguarding feeders and branch circuits in commercial and light industrial applications.
• OEM-compatible construction ensures reliable fit with matching loadcenters and panelboards, simplifying retrofits and coordinated protection across panels.
• Versatile for multiple settings—well suited for commercial lighting and HVAC panels, data center feeders, and other three-phase circuits that demand sturdy, long-lasting protection.

Technical details

• Manufacturer: Square D
• Part Number: EJB34125
• Type: Thermal-magnetic molded case circuit breaker
• Amperage Rating: 125 A
• Voltage Rating: 480 V
• Number of Poles: 3
• Mounting Style: Bolt-on
• Application: Branch circuit overcurrent and short-circuit protection

Who benefits from the Square D EJB34125

Electricians, facilities managers, and electrical engineers who specification-search for durable, panel-ready protection will appreciate the combination of secure mounting, precise thermal-magnetic protection, and OEM compatibility. If you’re upgrading an existing panel or designing a new three-phase system, this breaker provides a trusted, industry-standard solution that aligns with typical commercial and light industrial electrical practices.

Practical tips and use cases

• Use in panelboards and loadcenters where a robust 3-pole protection device is required for 480 V three-phase circuits.
• Pair with compatible Square D OEM panels to ensure seamless integration and protection coordination across the entire distribution system.
• Install in environments with moderate vibration or where secure bus connections are critical to long-term reliability.
• Ideal for protecting feeders feeding motors, HVAC systems, lighting bus sections, and other critical three-phase loads.