Square D HJA36125UDYP 125A 3-Pole 600 V Circuit Breaker Potential Transformer

Powerful, compact, and built for reliability in demanding installations, the Square D HJA36125UDYP is a 125 A, 3-pole circuit breaker with an integrated potential transformer. Rated for 600 V, this device combines robust overcurrent protection with metering and protection-relay compatibility, making it an ideal choice for modern industrial and commercial power distribution systems.

Key specifications

• Part Number: HJA36125UDYP
• Current rating: 125 A
• Poles: 3
• Voltage rating: 600 V
• Integrated potential transformer for metering, relay inputs, and protection schemes
• Designed for use in Square D / Schneider Electric panels, switchgear, and feeders

Why this model stands out

• Integrated potential transformer reduces field wiring complexity, enabling streamlined protection and monitoring workflows.
• Three-pole configuration provides balanced protection for multi-phase circuits, ideal for motor feeders and distribution panels.
• 600 V system compatibility expands its applicability across heavy-duty electrical installations, from manufacturing lines to large HVAC and power distribution feeders.
• Precise protection with seamless compatibility with protective relays and metering equipment, helping you translate protection actions into actionable system insights.

Ideal use scenarios

Use the Square D HJA36125UDYP for serving critical loads in industrial environments, including motor feeders, large lighting and climate control circuits, and other multi-phase distribution paths. It’s particularly well-suited where reliable protection must be paired with accurate real-time monitoring through a potential transformer—enabling clearer diagnostics, easier maintenance, and improved system uptime.

Practical benefits and outcomes

• Faster installation with a single device that covers both protection and monitoring needs.
• Enhanced visibility into system conditions through the integrated transformer, supporting more informed decisions during startup, load shifts, and fault events.
• Reduced wiring density and simplified panel layouts, freeing space in crowded electrical rooms.

What to know before you buy

Ensure your distribution setup requires a 125 A, 3-pole device with a 600 V rating and that your protection strategy can leverage an integrated potential transformer for metering and relay interfacing. This model is a practical choice for facilities aiming to streamline protection schemes while maintaining robust, scalable protection for feeders and large loads.