Square D QOB330AS 330A 3-Pole 240 V Circuit Breaker Potential Transformer

Meet the Square D QOB330AS 330A 3-Pole 240 V Circuit Breaker with Potential Transformer — a purpose-built protection solution for demanding three-phase power systems. With a robust 330 A current rating and a 3-pole configuration, this unit is engineered to safeguard large feeders and heavy loads while enabling precise electrical monitoring through its potential transformer capabilities.

Key specifications at a glance

• Part Number: QOB330AS
• Current rating: 330 A
• Poles: 3
• Voltage rating: 240 V
• Configuration: 3-pole circuit breaker designed for three-phase protection
• Potential transformer readiness: engineered to integrate with measurement and protection schemes for remote monitoring and relay interfaces

Why this model stands out

• at 330 A, it’s tailored for sizable feeders and motors without sacrificing reliability.
• Potential transformer integration: the design supports accurate voltage and current sensing feeding metering systems or protective relays, simplifying monitoring and diagnostic workflows.
• Brand reliability and ecosystem compatibility: built to align with Square D panels and components, making replacement and upgrades straightforward within existing Square D installations.

Ideal use cases

• Industrial facilities protecting large motors, conveyors, or heavy equipment that run on three-phase power.
• Power distribution panels in manufacturing lines where real-time monitoring and protective interlocks are critical.
• Commercial or data-center environments requiring robust overcurrent protection with integrated monitoring capabilities.

How to use it effectively

• Pair the QOB330AS with compatible Square D panels that accept QOB-series breakers to ensure optimal fit and electrical performance.
• Leverage potential transformer integration to feed accurate signals to metering systems and protective relays, enabling proactive protection and easier fault tracing.
• Follow standard installation practices for three-phase breakers in three-pole configurations, ensuring proper wiring, secure terminations, and compatibility with your distribution scheme.

Whether you’re upgrading an aging protection scheme or designing a new three-phase distribution network, the Square D QOB330AS 330A 3-Pole 240 V Circuit Breaker with Potential Transformer delivers precise protection, reliable operation, and seamless integration with monitoring systems — helping you protect critical loads while simplifying measurement and maintenance tasks.