Square D HJA36125SDYP 125A 3-Pole 600 V Circuit Breaker Potential Transformer

Meet the Square D HJA36125SDYP 125A 3-Pole 600 V Circuit Breaker with Potential Transformer — a purpose-built protection solution for demanding three-phase systems. This part delivers reliable overcurrent protection at a robust 125 A rating while supporting integration with a potential transformer for precise voltage sensing and smarter monitoring in industrial panels.

Key specifications

• Current rating: 125 A
• Poles: 3
• Voltage rating: 600 V
• Part number: HJA36125SDYP
• Brand: Square D (Schneider Electric)

Why this 3-pole unit stands out

• Three-pole design ensures balanced protection across all three phases, helping prevent motor damage and voltage imbalances in demanding equipment environments.
• 125 A rating is well-suited for medium-load circuits, making it an ideal choice for motor feeders, distribution panels, and equipment racks.
• 600 V maximum system voltage supports a wide range of industrial wiring configurations and future expansion plans.
• Potential Transformer compatibility enables accurate voltage measurement for metering, protection relays, and remote monitoring, reducing the complexity and risk of high-voltage sensing.
• Built to align with Square D ecosystems, ensuring reliable performance and seamless integration with existing Square D panels and accessories.

Ideal use cases

This breaker shines in motor control centers (MCCs), switchgear assemblies, and distribution boards where reliable three-phase protection and voltage monitoring are essential. It’s a strong fit for manufacturing lines, data centers, and large commercial or industrial facilities that rely on dependable protection and scalable monitoring solutions.

How it helps your operation

• Protects critical feeders, motors, and transformers from overloads and short circuits, reducing downtime and maintenance costs.
• Leverages potential transformer integration to support accurate voltage sensing, enabling smarter protection schemes and energy management.
• Streamlines upgrades and replacements with a trusted Square D part, helping maintain system compatibility and reducing commissioning time.

Installation and care tips

Confirm panel compatibility and adhere to applicable electrical codes. Use proper torque on terminal connections, verify system voltage matches the breaker’s rating, and replace with the same part number during service to maintain listing and reliability. Pair with compatible Square D accessories designed for HJA36125SDYP installations to maximize performance and ease of maintenance.