Siemens Q120DF Dual Function Miniature Circuit Breaker
- 20A
- 1 Pole
- Plug-On
Quantity
Siemens Q120DF - 20A Dual Function Miniature Circuit Breaker
New
Quantity
Description
Combining two critical safety functions into one device, the Siemens Q120DF provides both combination arc fault and 5mA ground fault protection. This 20-amp, single-pole breaker utilizes a standard pigtail neutral connection, making it compatible with legacy and current Siemens load centers that lack a plug-on neutral bar. Featuring a 10kAIC rating at 120VAC, it includes intuitive LED trip indicators to help electricians quickly diagnose the specific cause of a circuit interruption.Specifications
| Brand | Siemens |
|---|---|
| Part Number | Q120DF |
| Series | Q |
| Amperage | 20A |
| Poles | 1 |
| Mounting Style | Plug-On |
| Voltage | 120VAC |
| Phase | 1 |
| AIC Rating | 10kA @ 120VAC |
| Frame Type | Q |
|---|---|
| Terminal Type | Lugs |
| For Use With | Siemens Load Centers |
| Wire Gauge | 14-8 AWG (Cu), 12-8 AWG (Al) |
| Max Wire | 8 AWG |
| Min Wire | 14 AWG (Cu), 12 AWG (Al) |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LIG |
| Trip Function | Long-Time, Instantaneous, Ground Fault |
| Trip Adjustability | Fixed |
| Special Classification | Dual Function (AFCI/GFCI) |
|---|---|
| Available Options | Padlock Attachment |
| Accessories | Pigtail Neutral (Factory Installed) |
| Standards | HACR, SWD, UL 1699, UL 489, UL 943 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | Insta-Wire, HACR Rated, SWD Rated, Self-Test, Visual Trip Indicator |
Product FAQs
7 answersDoes the Q120DF require a plug-on neutral load center?
No. This breaker features a pigtail neutral wire, making it compatible with both legacy and modern Siemens load centers, even if the panel does not have a plug-on neutral bar.
How is the neutral wired on this pigtail-style breaker?
The coiled white pigtail wire must be connected directly to the panel's neutral bus bar. The branch circuit's neutral wire is then landed on the breaker's designated neutral lug alongside the hot wire.
What specific hazards does this dual-function breaker protect against?
It provides Combination Arc Fault (CAFCI) protection to detect dangerous arcing that can cause fires, alongside 5mA Class A Ground Fault (GFCI) protection to prevent severe electrical shock to personnel.
What is the difference between the Siemens Q120DF and Q120DFN?
The Q120DF includes a factory-installed pigtail neutral wire for use in standard panels. The Q120DFN is the Plug-On Neutral (PON) version, which lacks the pigtail and requires a compatible Siemens PON load center.
Can I install this Siemens breaker in a Square D or GE panel?
No. The Q120DF is designed exclusively for Siemens load centers and approved legacy ITE or Murray panels. Mixing breaker brands violates UL listings and compromises panel safety.
How do I use the LED trip indicators on this breaker?
The Q120DF features exclusive LED indicators that provide diagnostic information. After a trip, observing the LED light pattern helps you quickly identify whether the circuit tripped due to an arc fault, a ground fault, or an overcurrent condition.
Can this breaker be used for HVAC equipment or switching lighting circuits?
Yes. It is HACR rated for heating, air conditioning, and refrigeration applications, and SWD rated for switching duty on 120V fluorescent lighting circuits.
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Reviews
Review summary
Customers rate this product 5.0 out of 5 based on 47 reviews.
- CGCrocefissa G.Verified BuyerReviewingSiemens Q115 - 15A 1 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars9/18/26Quick delivery and great price.
The circuit breakers are at a great cost.
- JBJason B.Verified BuyerReviewingSiemens Q2150B - 150A 2 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars9/18/26Great experience
The product was exactly what I needed and it arrived on time.
- DQDon Q.Verified BuyerReviewingSiemens Q3100 - 100A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars9/14/26Siemens breaker
Great customer experience, great prices and fast shipping... Definitely will be buying her again.
- CSChristopher S.Verified BuyerRated 5 out of 5 stars8/12/26Siemens 60
Perfect new condition
- GSGeorge S.Verified BuyerReviewingSiemens Q2150B - 150A 2 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars3/4/26Great service
Every time I call or go online you have the parts I'm looking for.