Engineered for residential power management, the Siemens Q21515CTNC combines two 1-pole 15A circuits and one 2-pole 15A circuit into a compact 2-inch module. This allows installers to add branch circuits without upgrading the entire enclosure. Designed as a non-CTL breaker without rejection clips, it mounts into older Siemens EQ, EQL, SEQ, and EQG load centers. The plug-on design ensures a secure connection. The center poles share a common trip mechanism for reliable 240V protection.
What type of load centers accept the Q21515CTNC breaker?
This Non-CTL breaker is designed for older, pre-1968 Siemens, ITE, and Gould load centers that do not feature Circuit Total Limiting (CTL) rejection tabs. It is intended strictly for replacement use in these legacy panels.
Can I install this Non-CTL breaker in a modern Class CTL panelboard?
No. Installing a Non-CTL breaker in a modern Class CTL panelboard violates the UL listing of the assembly. This breaker lacks the rejection clip found on CTL breakers and is strictly for use in older, non-limiting panels.
How many panel spaces are required to install this breaker?
This quad-style breaker requires two standard 1-inch panel spaces. It consolidates two independent 1-pole 15A circuits and one shared 2-pole 15A circuit into a compact footprint.
How are the voltages distributed across the poles on this breaker?
The two outer poles operate as independent 120V single-pole circuits. The two inner poles are tied together with a common trip mechanism to provide a single 240V double-pole circuit.
Do the inner and outer circuits share a trip mechanism?
The inner 2-pole 15A circuit features a common trip mechanism, ensuring both legs disconnect simultaneously during an overcurrent event. The two outer 1-pole 15A circuits operate and trip independently of each other and the inner circuit.
Is this a direct replacement for legacy ITE or Gould breakers?
Yes. Siemens acquired the ITE and Gould electrical distribution product lines. This breaker is the direct, UL-listed replacement for older ITE and Gould quad breakers requiring a Non-CTL configuration.
Does the Q21515CTNC provide arc fault or ground fault protection?
No. This unit is a standard thermal-magnetic breaker that provides only overload and short-circuit protection. It does not include AFCI or GFCI circuitry.
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Reviews
Review summary
Customers rate this product 5.0 out of 5 based on 47 reviews.
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Reviews Summary
Generated by AI from 91 most recent customer reviews
Last updated 8/1/25
Customers say these circuit breakers arrive quickly and match their specifications perfectly. Many reviews mention success finding hard-to-locate specialty breakers through this supplier. Common feedback includes praise for the accurate product descriptions, reliable shipping, and competitive pricing. While some note occasional stock limitations, users consistently report the breakers fit and function as intended.