We take cryptocurrency — so the coins you hold can buy real hardware.Pay in crypto, spend it on real hardware. Free insured shipping worldwide over $399. Plain, unbranded boxes, sent from Germany.Free insured shipping over $399. Your rate is locked for 30 minutes once checkout opens.Rate locked 30 minutes. Every item sealed, serial-checked and covered by a 24-month warranty.Sealed, 24-month warranty.

Saved items Sign in
Siemens BQ2B100 two-pole breaker, bolt-on mount, grey toggle, 3.8 by 4.6 by 12.9 inches

SIEMENS

SIEMENS BQ2B100 Miniature Circuit Breaker 100A 2 Pole 120/240V

SKU CH-HY48-BMF2B

Protects circuits up to 100 A at 120/240 V AC with a 10 kA interrupting rating in a bolt-on, two-pole frame

  • Protects circuits up to 100 A with 10 kA interrupting rating
  • Fits Siemens panelboards using bolt-on mounting style
  • Operates reliably up to 104 °F maximum temperature
  • Accepts 2 AWG aluminium or 4 AWG copper conductors
  • Compact 3.8 in length suits tight panel spaces

Application fit

The SIEMENS BQ2B100 is a 100 A two-pole miniature circuit breaker for single-phase 120/240 V AC panels. It protects branch circuits in residential or light-commercial installations that run on Siemens BQ-series panelboards. Builders needing DC protection or a higher interrupting class must look elsewhere.

Capacity and headroom

Rated at 100 A with a 10 kA interrupting rating at 120/240 V AC, the breaker handles typical heavy-duty branch loads such as large appliances or sub-panel feeds. The 125 A frame size gives a small margin above the trip rating, but the device is not rated for DC circuits and will not suit loads exceeding its 100 A thermal limit.

Build integration

Bolt-on mounting secures the unit directly to compatible Siemens panelboards without extra hardware. Lug terminals accept aluminium conductors down to 2 AWG or copper down to 4 AWG, simplifying wire termination. The 3.8 in by 4.6 in footprint and 12.9 in depth fit standard panel cavities, while the 104 °F maximum operating temperature covers normal indoor environments.

How it compares

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

Price $298.99
Pricier than about 87% of the 1,135 comparable items (median $54.99).

Specifications

Product
Brand nameSIEMENS

Questions about this item

Will the 100 A, 2-pole BQ breaker fit on the existing bolt-on bus in my Siemens panel?

Yes, it uses a bolt-on mounting style and a 125 A BQ frame that matches Siemens panelboards designed for that frame size.

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

Switch the toggle actuator to the on position; the breaker should carry up to 100 A continuously and trip only when current exceeds its standard trip curve within the 10 kA interrupting rating at 120/240 V AC.

What comes in the box and what must I supply for the wire connections?

The breaker itself is supplied; you must provide lug terminals and conductors no smaller than 4 AWG copper or 2 AWG aluminium to meet the terminal connection requirements.

More in Breakers & Circuit Protection

Similar items