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Siemens QF240A two-pole plug-in breaker, grey plastic housing with toggle actuator

SIEMENS

SIEMENS QF240A Circuit Breaker 40A 2 Pole 120/240V AC

SKU CH-ZZRQ-S8SRK

Plug-in ground-fault interrupter rated 40 A at 120/240 V AC with 10 kA interrupting capacity for Siemens load centres

  • Class A ground-fault protection trips at 5 mA
  • 40 A two-pole breaker handles 120/240 V AC loads
  • 10 kA interrupting rating at 120 V AC
  • Plug-in mounting fits Siemens load centres
  • Accepts 8 to 6 AWG copper conductors

SIEMENS QF240A 40A Ground Fault Breaker

The SIEMENS QF240A is a 40A two-pole miniature circuit breaker rated for 120/240V AC single-phase service. It provides Class A ground-fault protection with a 5mA trip threshold and a 10kA interrupting rating at 120V AC. The plug-in design fits compatible Siemens load centres and accepts 8 to 6 AWG copper conductors via lug terminals. Its frame size is rated at 225A.

Suits panels needing 5mA ground-fault protection

This breaker serves circuits where personnel protection against ground faults is required by code, such as bathrooms, kitchens, garages or outdoor receptacles fed from a Siemens load centre. It will not suit installations that demand standard overcurrent protection only, panels from other manufacturers, three-phase distribution systems or DC circuits. Buyers needing a higher interrupting rating or a different mounting style should look elsewhere.

Sustained load performance with 10kA interrupting

Under continuous loading the device operates within its 40A thermal rating while the ground-fault sensor monitors leakage current at the 5mA level. The 10kA AIR rating at 120V AC ensures safe interruption of available fault current on the protected circuit. The toggle actuator provides a clear visual indication of tripped status after an overload or ground-fault event. The plug-in mounting maintains secure contact during thermal cycling.

Highlights

  • Class A ground-fault protection trips at 5 mA
  • 40 A two-pole breaker handles 120/240 V AC loads
  • 10 kA interrupting rating at 120 V AC
  • Plug-in mounting fits Siemens load centres
  • Accepts 8 to 6 AWG copper conductors

Specifications

BrandSIEMENS

Questions about this item

What load-center series must I already have for this QF-series breaker to fit?

This QF-series breaker is designed for use with Siemens load centers, plugging directly into the panel bus.

Will the 10 kA interrupting rating at 120 V AC coordinate with older 10 kA breakers already in my panel?

Yes, the 10 kA AIR rating at 120 V AC matches the rating of many existing Siemens breakers, allowing consistent coordination.

How can I verify the ground-fault protection is active after installation?

Press the built-in test button; the toggle should trip to the middle position, confirming the 5 mA Class A GFCI function is working.

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