SIEMENS
SIEMENS BQ3B100 Miniature Circuit Breaker 100A 3 Pole 240V AC
Three-pole miniature circuit breaker rated 100 A at 240 V AC with 10 kA interrupting capacity, bolt-on mounting for Siemens panelboards
- 100 A three-pole protection for 240 V AC circuits
- 10 kA interrupting rating handles high fault currents
- Bolt-on mounting fits Siemens panelboards directly
- Lug terminals accept 4 AWG copper to 1/0 AWG conductors
- Compact 3.7 in depth suits tight enclosure spaces
Three-pole protection for 240 V panels
The SIEMENS BQ3B100 is a bolt-on miniature circuit breaker rated at 100 A for three-phase 240 V AC systems. It fits Siemens panelboards with a BQ frame size of 125 A and provides standard overcurrent protection for commercial and light-industrial distribution boards.
10 kA interrupting capacity at 240 V
The breaker carries a maximum AIR rating of 10 kA at 240 V AC, giving reliable fault clearance for typical panelboard short-circuit levels. It is not rated for DC applications, so it must only be used on AC circuits where the prospective fault current does not exceed this value.
Bolt-on mounting with lug terminals
The unit measures 3.7 in long, 4.5 in wide and 12.9 in deep, mounting directly onto the panelboard bus via bolt-on lugs. Terminals accept aluminium conductors from 2 AWG up to 1/0 AWG and copper from 4 AWG up to 1/0 AWG, with a maximum operating temperature of 104 °F.
Highlights
- 100 A three-pole protection for 240 V AC circuits
- 10 kA interrupting rating handles high fault currents
- Bolt-on mounting fits Siemens panelboards directly
- Lug terminals accept 4 AWG copper to 1/0 AWG conductors
- Compact 3.7 in depth suits tight enclosure spaces
Specifications
| Brand | SIEMENS |
|---|
Questions about this item
Will the 100 A, 3-pole BQ breaker coordinate with a 125 A main breaker already in my Siemens panelboard?
Yes, the BQ3B100 is rated for 100 A with a 10 kA interrupting capacity at 240 V AC and fits the 125 A frame size used in Siemens panelboards, so it will coordinate with a 125 A main.
How can I confirm the breaker is functioning correctly once it is bolted into the panel?
After installation, switch the toggle to ON and measure 240 V AC across each of the three poles with a multimeter; the toggle should stay firmly in the ON position under normal load up to 100 A.
Does the package include the lug terminals for 2 AWG aluminium or 4 AWG copper conductors, or must they be purchased separately?
The breaker comes with integral lug terminals that accept 2 AWG aluminium up to 1/0 AWG copper, so no separate lugs are required for wire sizes within that range.
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