Built to optimize residential panel space, the Siemens Q24040 is a quadplex breaker that provides two independent 40A circuits. By condensing four poles of protection into a two-pole footprint, it allows for system expansion without requiring a larger enclosure upgrade. This plug-on miniature breaker mounts into Siemens EQ, Ultimate, PL, and ES series load centers. It is replaced by the newer Q24040CT2 model. Rated for 10kA at 120/240VAC, it includes common trip functionality for both pairs.
Siemens Load Centers, EQ Load Centers, Ultimate Load Centers, PL Series Load Centers, ES Series Load Centers
Wire Gauge
8-6 AWG (Cu), 8-4 AWG (Al)
Max Wire
6 AWG (Cu), 4 AWG (Al)
Min Wire
8 AWG
Protection and operation
Trip Technology
Thermal Magnetic
Trip Function Code
LI
Trip Function
Long-Time, Instantaneous
Trip Adjustability
Fixed
Standards and features
Special Classification
Quadplex
Available Options
Padlock Attachment
Standards
HACR, UL 489
Approval
CSA, UL
Temp Rating
40C
Construction Features
Space Saver, HACR Rated, Common Trip
Product FAQs
7 answers
Which load centers are compatible with the Siemens Q24040 quad breaker?
This plug-on breaker mounts into Siemens EQ, Ultimate, PL, and ES series load centers. Your specific panel must be rated to accept CTL-type QT breakers, which can be verified on the enclosure's wiring diagram.
Are the Q24040 and Q24040CT2 the same breaker?
Yes, Q24040CT2 is the current catalog number for the Q24040. Both refer to the exact same Siemens 40/40A quadplex circuit breaker.
How much panel space does this quadplex breaker require?
The Q24040 requires two standard 1-inch panel spaces (2 inches total). By condensing four poles into a two-pole footprint, it provides two independent 40A 240V circuits without needing a larger enclosure.
Does this breaker feature common trip functionality?
Yes, it features internal common trip mechanisms for both 40A double-pole pairs. This ensures that both legs of the connected 240V circuit will trip simultaneously during an overload or short circuit.
Is the Siemens Q24040 suitable for HVAC applications?
Yes, this breaker is HACR rated, meaning it is approved for use with heating, air conditioning, and refrigeration equipment that requires a 40A circuit.
What wire sizes can be used with the Q24040 terminals?
The breaker lugs accept 8 to 6 AWG copper wire or 8 to 4 AWG aluminum wire. Always torque the connections to the manufacturer specifications printed on the breaker.
What type of protection does the Q24040 provide?
It utilizes thermal-magnetic trip technology to provide both long-time overload protection and instantaneous short-circuit protection for your branch circuits.
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Reviews
Review summary
Customers rate this product 5.0 out of 5 based on 4 reviews.
One of 2 circuits was damaged per corrosion. Installed new CB, fit up was exact and issue was rectified. CB arrived as promised, very reasonably priced and easy to find online.
RC
Rod C.
I recommend this product
Rated 5 out of 5 stars
3/10/21
It's a contactor...
Fast delivery. Good packaging. Good description, so I got what I wanted. ...and, they work.
What more could you ask for?
...not to mention SuperBreakers were the only ones to actually have stock, and at a slight to drastic cost reduction depending on who I compared them to.
AL
Alan L.
I recommend this product
Rated 5 out of 5 stars
10/21/18
Hard to Find Breaker
I had a particularly hard to find breaker, a tandem double pole 40A x 40A.
Lowes and Menards didn't have them so I went online and Superbreakers showed just what I needed in stock at a very reasonable price too. It's installed. May breaker panel has one slot with a non-tandem breaker remaining. Gee! I wonder if Superbreakers.net has triple-breakers?
JT
Jonathan T.
I recommend this product
Rated 5 out of 5 stars
10/11/17
Perfect solution to my home charging
Purchased this for the circuit panel for increasing the space. Worked perfectly.