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Siemens 5SY4120-5 Miniature Circuit Breaker - 1-Pole, A Curve, 20A

Siemens 5SY4120-5 Miniature Circuit Breaker

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ManufacturerSiemens

Part number5SY4120-5

Manufacturer Siemens

Part Number 5SY4120-5

Type Miniature Circuit Breaker

Poles 1

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Single pole 10kA interrupting rating Type A tripping characteristic 20A rated current 70mm modular width Very fast tripping for sensitive loads

Product description

The Siemens 5SY4120-5 is a single-pole miniature circuit breaker with a 20A rated current and a Type A tripping characteristic. It operates at 230/400V and has a 10kA breaking capacity. The Type A curve is designed for very fast tripping at low overcurrents, making it ideal for protecting sensitive electronic and semiconductor-based equipment.

This breaker is specifically designed for applications demanding rapid detection of even minor overcurrents, such as in telecommunications infrastructure, specialized electronic control systems, or instrumentation where component integrity is paramount. Its high amperage with a fast-acting curve is for unique protection scenarios.

Stanlo Automation, a veteran-owned distributor of industrial surplus, offers the Siemens 5SY4120-5. We are dedicated to providing essential components for your automation and control needs, ensuring availability and quality.

Technical specifications

Manufacturer	Siemens
Part Number	5SY4120-5
Type	Miniature Circuit Breaker
Poles	1
Rated Voltage	230/400 V
Breaking Capacity	10 kA
Tripping Characteristic	A
Rated Current	20 A
Width (D)	70 mm

Common applications

Sensitive Electronic Equipment

Semiconductor Protection

Telecommunications

Instrumentation

Specialized Control Systems

High-Amperage Sensitive Circuits

Compatible systems

Standard DIN rail mounting

Also known as

Siemens 5SY4120-5 MCB 5SY4 MCB 20A A-curve Siemens 1-pole fast trip 20A breaker

Replaces / compatible with

This 20A Type A circuit breaker is for applications requiring extremely fast overcurrent tripping for sensitive loads, suitable for replacing or upgrading specific Siemens 5SY4 series applications.

Technical note

Expert tip

The 5SY4120-5's Type A curve provides rapid tripping even at lower overcurrent multiples, making it critical for safeguarding advanced electronics and semiconductor-based systems where minimal current deviation can cause damage.

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Frequently asked questions

What makes the Siemens 5SY4120-5 with its 20A rating and Type A curve unique?

The Siemens 5SY4120-5 combines a higher 20A current rating with a Type A tripping curve, which is designed for extremely fast response to overcurrents. This combination is used in specialized applications to protect sensitive electronic components or semiconductor devices that require very rapid disconnection even at higher current levels.