CHINT NXM-400 S MCCB – 400A, 3 Pole, 50kA, Fixed Trip Unit

Premium Quality | Industrial & Commercial Electrical Protection

1. Product Description

The CHINT NXM-400 S Molded Case Circuit Breaker (MCCB) is a heavy-duty low-voltage circuit protection device designed for three-phase electrical distribution systems. It provides protection against overloads and short circuits in industrial and commercial installations.

Featuring a 400A rated current, three-pole construction, and a 50kA ultimate short-circuit breaking capacity, this breaker is suitable for appropriately engineered distribution panels, industrial feeders, and high-current electrical installations.

The fixed thermal-magnetic trip unit provides factory-defined protection characteristics, helping protect conductors and connected equipment when the breaker is correctly selected, installed, and coordinated.

2. Complete Technical Specifications

Important: Icu and Ics are different ratings. The cited CHINT catalog lists Icu = 50kA and Ics = 36kA for the NXM-400S/3300 400A, 3-pole version. Confirm the exact ratings on the current datasheet and product nameplate before using them in a project specification.

3. Electrical Protection Functions

Overload protection: The thermal release responds to sustained overcurrent conditions that may cause excessive heating of conductors and equipment.

Short-circuit protection: The magnetic release responds to high fault currents and trips the breaker to interrupt the circuit within its specified operating characteristics.

Circuit switching and isolation: The front operating handle allows manual switching. Follow safe isolation and lockout/tagout procedures before carrying out maintenance.

Fixed trip characteristics: The breaker is supplied with a fixed thermal-magnetic trip arrangement rather than an adjustable electronic trip unit.

4. Electrical Ratings Explained

• 400A rated current: The nominal current rating of this specific product variant. Actual allowable loading depends on ambient temperature, enclosure conditions, conductor sizing, and manufacturer derating requirements.
• 400AF frame size: Identifies the breaker frame class; the actual rated current of this listed variant is 400A.
• 50kA Icu: The rated ultimate short-circuit breaking capacity under the specified test conditions and operating voltage.
• 36kA Ics: The catalog-listed service short-circuit breaking capacity for the specified NXM-400S/3300 version.
• 380–415V AC: The operating-voltage range commonly listed for this three-pole version. Verify the precise rating for the supplied product.
• 50/60Hz: Suitable for systems operating at either frequency, subject to the product’s electrical ratings.

5. Construction and Design

The CHINT NXM MCCB series features a molded insulating enclosure and an integrated switching and tripping mechanism.

Key construction features include:

• Three-pole switching arrangement.
• Molded insulating case.
• Front-mounted manual operating handle.
• Line and load terminal connections.
• Integrated thermal-magnetic protection.
• Fixed trip configuration.
• Compact design for compatible industrial and commercial distribution panels.

Terminal dimensions, conductor capacity, tightening torque, clearances, and mounting dimensions should be obtained from the installation manual for the exact model.

6. Typical Applications

This MCCB can be considered for appropriately designed installations such as:

• Main low-voltage distribution panels.
• Industrial power distribution boards.
• Commercial building electrical systems.
• High-current feeder circuits.
• Manufacturing facilities and industrial machinery.
• Motor feeder circuits, with suitable motor-starting and protection coordination.
• Solar plant AC distribution and auxiliary circuits, where the electrical design and manufacturer ratings permit its use.
• Industrial control panels and sub-distribution systems.

The breaker must be selected according to the actual load, prospective fault current, system voltage, conductor ampacity, and protection coordination requirements.

7. Installation Requirements

Before installation, verify:

1. System voltage and frequency are within the breaker’s rated limits.
2. The prospective short-circuit current does not exceed the applicable Icu and Ics ratings.
3. Cable size and conductor material are compatible with the terminals.
4. Terminal tightening torque complies with the manufacturer’s instructions.
5. The enclosure provides suitable protection, ventilation, and clearances.
6. Upstream and downstream protective devices are coordinated correctly.
7. The installation is carried out by qualified electrical personnel with appropriate isolation and safety procedures.

8. Standards and Compliance

The CHINT NXM series is designed in accordance with IEC 60947-2 requirements for low-voltage circuit breakers.

For tender submissions, consultant approvals, and project documentation, verify the applicable conformity certificates, test reports, and exact model ratings for the supplied unit.

9. Product Benefits

• High short-circuit breaking capacity.
• Reliable thermal-magnetic protection when correctly applied.
• Three-pole configuration for three-phase distribution.
• Fixed trip unit for straightforward protection arrangements.
• Molded-case construction for industrial applications.
• Suitable for high-current distribution and feeder protection.
• Part of the CHINT NXM MCCB product family.

10. Product Identification

Full product name: CHINT NXM-400 S MCCB, 400A, 3P, 50kA, Fixed Thermal-Magnetic Trip

Manufacturer model: NXM-400S/3300 400A

Product code: 131373

Suggested VITS SKU: CHINT-NXM-400S-3P-400A-50KA

The suggested VITS SKU is for internal catalog organization and is not an official CHINT ordering code.

11. Website SEO Content

SEO title: CHINT NXM-400S MCCB 400A 3P 50kA | VITS Pakistan

Meta description: Explore the CHINT NXM-400S 400A, 3-pole MCCB with 50kA ultimate breaking capacity and fixed thermal-magnetic trip. Contact VITS for pricing, availability, and technical support.

Suggested URL slug: /products/chint-nxm-400s-mccb-400a-3p-50ka

Focus keywords: CHINT MCCB 400A, NXM-400S/3300, 3-pole MCCB, 50kA MCCB, fixed-trip MCCB, 400AF circuit breaker, CHINT MCCB Pakistan.

12. Commercial Information

For current pricing, stock availability, delivery lead time, and project or bulk-order quotations, contact VITS.

VITS – Versatile Industrial Trading & Services

Engineering • Trading • Complete Industrial Solutions

The molded case circuit breaker will provide protection for the circuit and equipment
in case of overload, short circuits and under-voltage conditions occurred in the power
distribution circuit. Besides, it can also provide protection of overload, short circuits and
under voltage for the non-frequent start of the motor

Certificates: KEMA, ESC, UKrSEPRO, PCT, RCC, KC
Electric Ratings: AC 690V, 50/60Hz
Standard: VITS/EN 60947-2
Frame Size: 63A, 125A, 160A, 250A, 400A, 630A, 800A, 1000A, 1250A, 1600A
Installation Method: Fixed Type; Plug-in Type