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Square D SFA1040A Molded Case Circuit Breaker

  • 40A
  • 1 Pole
  • I-Line
Square D SFA1040A
Molded Case Circuit Breaker
Brand Square D
SKU SFA1040A
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  • 40A
  • 1 Pole
  • I-Line

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Square D SFA1040A - 40A 1 Pole Molded Case Circuit Breaker

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$70.57 In Stock

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Description

Designed to handle heavy electrical loads, the Square D SFA1040A is a 1-pole, 40A molded case circuit breaker. It provides essential thermal-magnetic protection with long-time and instantaneous (LI) trip functions. This unit mounts into Square D I-Line panelboards and can replace legacy FA14040A breakers. Featuring a 25kA AIC rating at 240VAC and a factory-configured Phase A connection, this IEC-rated breaker ensures reliable performance in commercial facilities.

Specifications

Key specifications
Brand Square D
Part Number SFA1040A
Series SFA
Amperage 40A
Poles 1
Mounting Style I-Line
Voltage 240VAC
Phase 1
AIC Rating 25kA @ 240VAC
Fit and installation
Frame Type F
Terminal Type Lugs
For Use With Square D I-Line Panelboards
Wire Gauge 14-1/0 AWG
Max Wire 1/0 AWG
Min Wire 14 AWG
Protection and operation
Trip Technology Thermal Magnetic
Trip Function Code LI
Trip Function Long-Time, Instantaneous
Trip Adjustability Fixed Thermal, Fixed Magnetic
Standards and features
Available Options Shunt Trip, Auxiliary Switch, Alarm Switch
Accessories Phase A Connection (Factory Configured)
Standards IEC 60947-2, UL 489
Approval IEC, UL
Temp Rating -25C to 70C
Construction Features IEC Rated, Non-Interchangeable Trip, Phase A Connection

Product FAQs

6 answers
What panelboards are compatible with the Square D SFA1040A?

This breaker is designed specifically for Square D I-Line panelboards and switchboards. It is not compatible with NQ, NF, or standard residential QO load centers.

How does the SFA1040A mount into the panel?

It utilizes the Square D I-Line style plug-in connection. The breaker plugs directly onto the I-Line bus stack, which allows for rapid installation and eliminates the need for bolted bus connections.

What wire sizes can be used with the SFA1040A lugs?

The factory lugs on this breaker accept wire gauges ranging from 14 AWG up to 1/0 AWG.

What type of protection does the SFA1040A provide?

It features a fixed thermal-magnetic trip unit. The thermal mechanism responds to sustained overloads, while the magnetic mechanism provides instantaneous tripping during short-circuit events.

What does the 25kAIC rating indicate for this breaker?

The 25kAIC rating means the breaker can safely interrupt a fault current of up to 25,000 amps at 240V AC. This high interrupting capacity helps protect downstream equipment during severe short circuits.

Can I adjust the trip settings on the SFA1040A?

No, this breaker features a fixed thermal and fixed magnetic trip unit. The trip settings are factory-calibrated and cannot be adjusted in the field.

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