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Siemens 5SJ4240-7HG42 2-Pole C-Curve 40A Circuit Breaker

Siemens 5SJ4240-7HG42 2-Pole, 40A, C-Curve Miniature Circuit Breaker.

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ManufacturerSiemens

Part number5SJ4240-7HG42

Number of poles 2

Rated current 40 A

Tripping characteristic C

Breaking capacity 10 kA

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2-pole circuit protection C-curve tripping characteristic 40A current rating 10kA breaking capacity UL 489 compliant Industrial grade protection

Product description

The Siemens 5SJ4240-7HG42 is a 2-pole miniature circuit breaker featuring a C-curve tripping characteristic and a 40A rated current. It provides a 10kA short-circuit breaking capacity and is certified according to UL 489 standards for 480Y/277V electrical systems.

This circuit breaker is suitable for general-purpose applications in industrial and commercial settings, offering protection for circuits with moderate inrush currents. The C-curve provides a balance between overcurrent protection and accommodating transient surges common in some equipment.

Stanlo Automation, a veteran-owned business, is your reliable source for surplus industrial automation components. We offer the Siemens 5SJ4240-7HG42 with competitive pricing and swift delivery to support your maintenance and operational needs.

Technical specifications

Number of poles	2
Rated current	40 A
Tripping characteristic	C
Breaking capacity	10 kA
Voltage rating	480Y/277V AC
Standard	UL 489

Common applications

Commercial electrical panels

Industrial distribution boards

Machinery control

Lighting circuits

Power outlets

General purpose circuits

Compatible systems

Standard DIN rail mounting systems Siemens 5SJ4 series accessories

Also known as

Siemens 40A 2-pole C-curve breaker, 5SJ42407HG42, Siemens 5SJ4 40A

Replaces / compatible with

Compatible with Siemens 5SJ4 Series accessories and related components.

Technical note

Expert tip

The C-curve is generally suitable for protecting circuits containing equipment with low to moderate surge currents, like lighting and socket outlets.

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Frequently asked questions

What are typical applications for a Siemens 5SJ4240-7HG42 C-curve circuit breaker?

The Siemens 5SJ4240-7HG42 C-curve breaker is ideal for circuits with moderate inductive loads or in applications where brief inrush currents are expected, such as lighting and general power distribution in industrial and commercial settings.