ABB 3P250A Plastic Case Circuit Breaker 1SDA053999R1

1. Core functions

Circuit protection:

Overload protection: The thermal release (bimetallic strip) senses current overload and delays circuit disconnection to prevent overheating of the wire.

Short circuit protection: The magnetic release (electromagnetic coil) acts instantly when the current rises suddenly, cuts off the short circuit current, and prevents equipment damage and fire risks.

On-off control:

Manual operating handle (with position indication: ON/OFF/test), some models support electric operating mechanism (such as ABB MX or MN accessories) to achieve remote opening and closing.

Isolation function:

After disconnection, it meets the electrical isolation requirements (in accordance with IEC 60947-2), and the handle can be padlocked to prevent misoperation and ensure maintenance safety.

2. Structural design

Material of plastic shell:

The shell is made of thermosetting plastic (such as epoxy resin or polyester material), which has the characteristics of high temperature resistance, impact resistance, flame retardancy (in accordance with UL94 V-0) and so on.

Arc extinguishing system:

ABB's patented rotating arc extinguishing chamber technology guides the arc into the arc extinguishing grid through a magnetic field, quickly extinguishes the arc, reduces contact wear, and improves disconnection reliability.

Accessory extension:

Auxiliary contact (AUX): used to feedback the circuit breaker status (such as opening and closing signals) to the control system.

Alarm contact (ALM): triggers an alarm signal when tripping, which is used for fault warning.

Shunt release (MX): remote tripping through an external voltage signal (such as fire linkage).

Undervoltage release (MN): automatically trips when the voltage is abnormal to protect the load equipment.

3. Performance advantages

Compact design: The width of the 3-pole structure is usually less than 100mm, which saves space in the distribution cabinet and is suitable for dense installation.

High reliability: Passed rigorous life tests (such as 10,000 mechanical operation cycles), suitable for high switching frequency scenarios.

Energy saving and low loss: The low-energy release design is adopted to reduce energy loss in standby mode.

3. Application scenarios

1. Typical applications

Industrial power distribution system:

As a protective switch for motor circuits, inverter input lines or production line branch circuits, for example, to control three-phase motor loads in industries such as chemical, food processing, and metallurgy.

Commercial and building electrical:

Installed in distribution boxes or load centers, used for three-phase lighting, air conditioning or power equipment distribution in shopping malls, office buildings, hotels and other places.

Renewable energy field:

Provide overload and short-circuit protection on the DC or AC side of solar photovoltaic inverters and wind power converters (need to confirm whether DC applications are supported).

2. Not applicable to scenarios

DC high-voltage system: Unless the model is specifically marked with "DC", it is used for AC systems by default. For DC scenarios, a dedicated DC molded case circuit breaker (such as ABB Isomax DC series) must be selected.

High-current main input line: The 250A specification is usually used as a branch circuit protection. It is recommended to select a circuit breaker with a higher frame current (such as 630A and above) for the main input line.