SQUARE D
SQUARE D QO310 10A 3 Pole 120/240V AC circuit breaker
Three-pole miniature circuit breaker rated 10 A at 120/240 V AC with 10 kA interrupting capacity, plug-in mounting for QO load centres and NQ panelboards
- Protects three-phase circuits with 10 A rating and 10 kA interrupting capacity
- Fits QO load centres and NQ panelboards via plug-in mounting
- Handles 120/240 V AC and 48 V DC systems in one device
- Pressure-plate terminals give secure connections without special tools
- Compact 3 in × 2.3 in × 2.9 in frame suits tight panel space
Three-pole protection for 120/240 V panels
The Square D QO310 is a plug-in miniature circuit breaker built for QO load centres and NQ panelboards. It delivers standard thermal-magnetic protection on three-phase circuits rated at 120/240 V AC and 48 V DC.
10 A trip rating defines the circuit limit
The single specification that decides fit is the 10 A ampere rating. Only circuits designed for a 10 A continuous load should use this breaker; any higher demand requires a different rating.
Handles 10 kA fault current within a 100 A frame
Rated for a maximum AIR of 10 kA at 120/240 V AC, the device fits a 100 A frame size and measures 3 in long, 2.3 in wide and 2.9 in deep. It is not suited for systems needing higher interrupting capacity or a larger frame.
Highlights
- Protects three-phase circuits with 10 A rating and 10 kA interrupting capacity
- Fits QO load centres and NQ panelboards via plug-in mounting
- Handles 120/240 V AC and 48 V DC systems in one device
- Pressure-plate terminals give secure connections without special tools
- Compact 3 in × 2.3 in × 2.9 in frame suits tight panel space
Specifications
| Brand | SQUARE D |
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Questions about this item
What does the 10 A rating mean once the breaker is installed in a panel?
It will carry up to 10 A continuously on each of the three poles and trip if that current is exceeded, protecting the connected circuits.
What does the 10 kA AIR rating at 120/240 V AC cap in practice?
It means the breaker can safely interrupt fault currents up to 10 kA on a 120/240 V AC system without damage.
What physical space and mounting style does the QO310 need to fit in a load center?
It uses a plug‑in mount, measures 3 in long, 2.3 in wide and 2.9 in deep, and fits QO‑series load centres with a 100 A frame size.
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