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SHT SM50-125R/3300 20A Molded Case Circuit Breaker

Brand:

SHT

Series:

SM50

Protection Type:

Main body (with protection function)

How It Works:

Manual

Frame Current:

125A

Tripping Mode:

Thermal Magnetic

Protection Function:

Wiring Method:

Front panel wiring

Poles:

Rated Voltage:

400VAC

Installation:

Fixed

Trip Unit:

Compound release

Rated Current of Release:

20A

Breaking Capacity:

100KA

Model:

SM50-125R/3300 20A

Order Number:

Description:

SHT Molded Case Circuit Breaker SM50-125R/3300 20A,LI,100KA,125A,Fixed,Manual,3P

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Product parameters
Series Overview

Product parameters

Product attributes	Attribute value	Filter product attributes
Brand：	SHT
Series：	SM50
Appendix：	-
Protection Type：	Main body (with protection function)
How It Works：	Manual
Frame Current：	125A
Tripping Mode：	Thermal Magnetic
Protection Function：	LI
Wiring Method：	Front panel wiring
Poles：	3P
Rated Voltage：	400VAC
Installation：	Fixed
Trip Unit：	Compound release
Rated Current of Release：	20A
Breaking Capacity：	100KA

Products with the same attribute : 0

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Series Overview

Scope of Application and Main Features

The SM50 series Molded Case Circuit Breakers (hereinafter referred to as the circuit breakers) are one of the SM50 series products, developed by our company utilizing advanced international design and manufacturing technology. Their rated insulation voltage is 800V, and they are suitable for circuits with AC 50Hz, rated operational voltage up to 690V, and rated operational current up to 800A, for infrequent switching and infrequent starting of motors. The circuit breakers feature overload, short-circuit, and undervoltage protection functions, protecting lines and power supply equipment from damage. Additionally, SM50-125~800 circuit breakers can have an overload alarm without tripping function and provide alarm contacts – one normally open (NO) or one NO and one normally closed (NC).

● This series of circuit breakers features a compact structure, small size, high breaking capacity, and a complete range of internal and external accessories.

● This series of circuit breakers has an isolation function, and its corresponding symbol is: [Symbol Placeholder - Note: Original symbol not provided in text].

Compliance Standards

● This series of circuit breakers complies with the following standards:

● IEC 60947-1, GB 14048.1 (General Rules)

● IEC 60947-2, GB 14048.2 (Low-voltage circuit-breakers)

● IEC 60947-4, GB 14048.4 (Contactors and motor-starters)

● IEC 60947-5-1, GB 14048.5 (Electromechanical control circuit devices).

Applicable Operating Environment

● The altitude of the installation site shall not exceed 2000m;

● The ambient air temperature is -5℃ to +40℃, and the average value over 24 hours shall not exceed +35℃ (Derating is required for temperatures greater than +40℃ up to +60℃);

● The relative humidity of the ambient air at the installation site shall not exceed 50% at the maximum temperature of +40℃; higher relative humidity is permissible at lower temperatures. The monthly average minimum temperature of the wettest month does not exceed +25℃, and the monthly average maximum relative humidity of that month does not exceed 90%, taking into account condensation occurring on the product surface due to temperature changes;

● Pollution degree is 3;

● The installation category for the main circuit of the circuit breaker is III, and for other auxiliary and control circuits, it is II;

● The circuit breaker shall be installed in locations without explosion hazards, conductive dust, or conditions sufficient to corrode metal and damage insulation;

● The circuit breaker shall be installed in locations free from rain and snow intrusion.

Installation Method

● This series of circuit breakers can be installed vertically or horizontally.

Operation and Maintenance

● The rated voltage, current, and short-circuit breaking capacity of the circuit breaker must meet the requirements of the electrical system. The long-time delay protection and instantaneous short-circuit protection characteristics must not be adjusted arbitrarily by opening the cover. The calibration temperature at the factory is +40℃.

● The wiring of the circuit breaker must follow the "top-in, bottom-out" principle, meaning terminals 1, 3, 5 are for the power supply lines and terminals 2, 4, 6 are for the load lines. Reverse feed (bottom-in) is not permitted; if bottom-in wiring is absolutely necessary, the breaking capacity of the circuit breaker must be reduced, generally by 20% to 30%.

● For circuit breakers equipped with an undervoltage release, the undervoltage release must be supplied with the rated voltage; otherwise, the circuit breaker may be damaged.

● The circuit breaker handle can be in three positions, indicating ON, OFF, and TRIPPED states respectively. When the handle is in the TRIPPED position, pull the handle backward to reset the trip mechanism, then close the circuit breaker.

● Provided the user adheres to the storage and operating conditions, and the seals are intact within 18 months from the date of shipment by the manufacturer, if there is a quality problem attributable to our company's production, we will be responsible for free replacement or repair.

Rachel

Industrial Control Sales Specialist: Focuses on delivering high-performance, cost-effective industrial control products. Offers end-to-end one-stop procurement support—covering rapid quotation, streamlined order fulfillment, and responsive after-sales service—to simplify clients’ procurement processes. Email: Anthony@icxsg.com

We offer competitive product pricing. For fast support, send your email, phone, address, and the product model & quantity you want—we’ll reach out quickly!

We typically respond via email within one business day! You can also contact us at Anthony@icxsg.com

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SHT SM50-125R/3300 20A Molded Case Circuit Breaker

Product parameters

Series Overview

Rachel

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