Siemens Q24040CT2 40/40A Quadplex Miniature Circuit Breaker

This Type QT breaker is compatible with Siemens EQ, Ultimate, PL, and ES series load centers that are designed to accept half-inch frame breakers. Check your panel's wiring diagram to confirm it accepts Type QT breakers.

The Q24040CT2 is the updated version of the legacy Q24040. The CT2 designation indicates it features internal common trip mechanisms on both the inner and outer 40A double-pole circuits. It also serves as the direct replacement for the legacy Murray MP24040CT2.

The Q24040CT2 requires two standard 1-inch panel spaces. By condensing four poles into a 2-inch footprint, it provides two independent 240V, 40A circuits, making it ideal for adding capacity to a crowded load center.

No. Because it is a CTL (Circuit Total Limiting) breaker, it is equipped with rejection features. It will only seat properly in panel bus bar slots that are specifically notched to accept tandem or quadplex breakers.

The internal common trip ensures that if an overload or short circuit occurs on one leg of either 40A double-pole circuit, both legs of that specific circuit will trip simultaneously. This prevents a partial power situation to 240V loads, ensuring safe operation.