Overview
The Siemens Q21530CT2 is a space-saving quadplex molded-case circuit breaker from the Q Series QT (Quad Tandem) family. This 2-pole breaker combines two independent common-trip double-pole circuits in a single two-space load center position, maximizing circuit density while maintaining reliable overload and short-circuit protection. Designed for plug-on installation in Siemens CTL and compatible load centers, it serves as a direct drop-in replacement for the MP21530CT2.
Key Features
- Quadplex Configuration: Inner 30A and outer 15A double-pole settings provide flexible amperage selection
- Common Trip Mechanism: Both circuit pairs use common-trip operation for coordinated protection
- Thermal-Magnetic Trip: LI (Long-Time and Instantaneous) functions deliver fast fault detection
- SWD Rating: 15A poles rated for switching fluorescent lighting loads
- Plug-In Connection: Direct installation with no wiring required
Technical Specifications
The breaker meets UL 489 standards and delivers proven performance in residential and commercial distribution applications.
Typical Applications
- Residential service panels and load centers
- Light commercial electrical distribution
- Fluorescent lighting circuit protection (15A poles)
- Space-constrained panel environments requiring maximum circuit density
Compatibility & Replacements
The Q21530CT2 fits Siemens CTL-series and Murray load centers rated for Type QT breakers. It is a direct replacement for the older MP21530CT2 model. Verify your load center nameplate for QT compatibility before ordering.
