CHINT NB2-40ZT Smart MCB 1P 6A-40A 6kA AC230V

Name: CHINT NB2-40ZT 1-Pole Smart Miniature Circuit Breaker 6A-40A 230V
Brand: CHINT

Description

CHINT NB2-40ZT Smart Miniature Circuit Breaker is a smart 1P MCB designed for final power distribution, remote monitoring and smart circuit protection. It combines conventional thermal-magnetic protection with communication and electrical measurement functions, making it suitable for intelligent distribution boards, smart homes, commercial buildings and light industrial control systems.

1. Product overview

The NB2-40ZT belongs to the CHINT NB2 Smart Series and is built for intelligent low-voltage protection. Compared with a conventional MCB, it adds communication, electrical parameter monitoring and configurable overvoltage / undervoltage protection, helping users achieve smarter circuit management without changing the standard DIN rail installation method.

2. Main features

Smart 1P miniature circuit breaker for digital distribution systems
Rated current options: 6A, 10A, 16A, 20A, 25A, 32A and 40A
Type C tripping curve for mixed residential and commercial load protection
Rated breaking capacity: 6kA
Rated voltage: AC230V
Communication protocol: Modbus-RTU via RS485
Supports remote supervision and integration with smart management platforms
Electrical parameter measurement for current, voltage and power
Overvoltage, undervoltage, over-frequency, under-frequency and open-phase protection markings shown in catalogue
Standard DIN rail mounting for easy retrofit and panel integration

3. Technical specifications

Item	Specification
Series	NB2-40ZT
Product type	Smart Miniature Circuit Breaker
Rated current	6A / 10A / 16A / 20A / 25A / 32A / 40A
Rated voltage	AC230V
Poles	1P
Tripping curve	Type C
Mechanical life	10,000 operations
Electrical life	6,000 operations
Rated breaking capacity	6kA
Rated insulation voltage	690V
Rated impulse withstand voltage	4kV
Frequency	50Hz
Communication	Modbus-RTU, RS485 A/B
Protection degree	IP20
Standard	DIN rail installation, smart MCB application

4. Smart protection functions

Overvoltage protection (OVP)
Undervoltage protection (UVP)
Over-frequency protection (OFP)
Under-frequency protection (UFP)
Open-phase protection (OPP)
Remote monitoring and communication-ready smart circuit management

5. Typical applications

Smart home distribution boards
Commercial and office distribution panels
Energy monitoring systems
Remote electrical control projects
Intelligent final power distribution systems

6. Available models

According to the catalogue, the NB2-40ZT 1P Type C series includes 6A, 10A, 16A, 20A, 25A, 32A and 40A options, all with 6kA breaking capacity and AC230V rating.

7. Ordering support

If you need help selecting the suitable NB2-40ZT current rating or integrating this smart MCB into your monitoring system, send us your current requirement, control method and communication needs. We can recommend the right model for your application.

8. Original catalogue pages

The following original catalogue pages are attached below for technical verification, dimensional reference and model selection.

Additional information

Poles	1P
Rated Current	6A, 10A, 16A, 20A, 25A, 32A, 40A
Tripping Curve	C
Breaking Capacity	6kA

Technical Datasheet & Downloads

📄 Technical Documentation & Product Specifications

Download official engineering datasheets, certified test standards (IEC / UL / CE), wiring diagrams, and dimensional drawings for CHINT NB2-40ZT 1-Pole Smart Miniature Circuit Breaker 6A-40A 230V.

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Official Technical Datasheet (PDF) Complete electrical ratings, tripping characteristics, dimensions, and compliance specifications.

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2D/3D CAD & Dimensional Drawings STEP, DXF, and PDF CAD drawing files for panel builders and switchgear designers.

Technical FAQ & Selection Guide

💡 Frequently Asked Technical Questions & Selection Guide

Pure engineering specifications, tripping curve parameters, and electrical selection guidance for panel builders and system designers.

Curve Selection

How to choose between Tripping Curves B, C, and D for this miniature circuit breaker?

Curve B trips at 3–5 In (designed for resistive loads, electric heating, and domestic appliances with negligible inrush). Curve C trips at 5–10 In (the standard international choice for residential and commercial lighting, socket outlets, and small induction motors). Curve D trips at 10–14 In (specifically engineered for high-inrush inductive equipment such as industrial transformers, heavy motors, compressors, and welding circuits).

Breaking Capacity

How do I determine whether 6kA or 10kA breaking capacity is required for my installation?

Breaking capacity (Icn/Icu) must exceed the calculated prospective short-circuit fault current at the installation point. 6kA (IEC 60898-1) is standard for residential consumer units and sub-distribution branch circuits located downstream. 10kA (IEC 60947-2) is required for industrial facilities, main switchboards, commercial distribution panels, or circuits situated close to supply transformers where fault levels are high.

Poles & Neutral Isolation

How to choose the correct number of poles (1P, 1P+N, 2P, 3P, 3P+N, 4P) for single-phase and three-phase circuits?

For single-phase 230V circuits: 1P provides active phase protection; 1P+N or 2P isolates both live and neutral lines simultaneously (essential for TT earthing systems and sensitive sub-panels). For three-phase 400V systems: 3P protects balanced 3-wire motor loads; 3P+N or 4P is required for 4-wire mixed single-phase loads to ensure complete neutral disconnection during isolation.

DC vs AC Application

Can this circuit breaker be used in DC circuits (Solar PV, Battery Storage, Telecom)?

Standard AC breakers cannot safely extinguish DC arcs due to the absence of natural zero-crossing current. For DC circuits (60V to 1000V DC), select specialized DC breakers (such as DZ158-125 DC or NM8NDC series) equipped with permanent magnetic arc-blowout chutes and strictly observe polarity wiring to prevent arc re-ignition.

Modular Accessories & Interlocks

What modular accessories and mechanical interlocks can be fitted to this breaker?

Standard modular clip-on accessories can be mounted directly on the side without tools: OF (Auxiliary Contact for remote status indication), SD (Alarm Contact for trip fault signaling), MX (Shunt Trip for remote emergency tripping), MN (Under-voltage Release for voltage loss protection), and NXBZ mechanical interlock kits for manual generator/mains transfer switches.