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Siemens Q140 single-pole breaker, grey toggle, plug-in mount

SIEMENS

SIEMENS Q140 Circuit Breaker 40A 1 Pole 120V AC 10kA

SKU CH-HTD8-SGQAX

Provides 40 A single-pole circuit protection at 120 V AC with a 10 kA interrupting rating for Siemens EQ load centres

  • 40 A single-pole protection for 120 V AC branch circuits
  • 10 kA interrupting rating handles high fault currents safely
  • Plug-in mounting fits Siemens EQ load centers directly
  • Toggle actuator gives clear on/off indication
  • Lug terminals accept 8 AWG to 4 AWG aluminium or 6 AWG copper

SIEMENS Q140 40 A Breaker

The SIEMENS Q140 is a single-pole miniature circuit breaker rated at 40 A for 120 V AC systems. It is designed for residential or light-commercial panels that use the Siemens EQ load-centre series and need standard over-current protection on one hot conductor.

40 A capacity and 10 kA interrupting

The breaker carries a continuous 40 A load and will safely interrupt up to 10 kA at 120 V AC, providing ample headroom for typical branch circuits such as lighting, receptacles or small appliance feeds. It is not suitable for loads exceeding 40 A, multi-pole applications or panels outside the EQ series.

Plug-in mounting with toggle actuator

The plug-in mounting style allows tool-free installation onto the panel bus, while the toggle actuator gives clear visual indication of the breaker state. Terminal lugs accept 8 AWG minimum up to 4 AWG aluminium or 6 AWG copper conductors, and the frame is rated within a 125 A/QP envelope for normal thermal performance.

How it compares

Measured against everything we stock in Breakers & Circuit Protection, at today’s prices. Recalculated every night.

Price $7.99
Cheaper than about 95% of the 1,135 comparable items (median $54.99).

Specifications

Product
Brand nameSIEMENS

Questions about this item

Will the Q140 40 A single-pole breaker fit in the EQ load centre I already have?

Yes — it is built for Siemens EQ load centres and uses a plug-in mounting style that matches the existing bus.

How can I confirm the breaker is operating correctly once installed?

Switch the toggle to ON; the handle should stay firmly latched and the circuit should carry load up to 40 A at 120 V AC without tripping.

Does the package include the lug terminals or do I need to buy them separately?

The breaker comes with a factory-fitted lug terminal that accepts 8 AWG to 4 AWG aluminium or 6 AWG copper conductors.

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