Chint's NXB series and DZ47 series

As representative products of low-voltage circuit breakers, the main differences between Chint's NXB series and DZ47 series are reflected in the following aspects:

 I. Product Positioning and Technical Iteration

DZ47 is a classic economical product of Chint, which is an early model imitating Schneider's C45 series and complies with GB/T 10963.1 and IEC 60898-1 standards. The NXB series belongs to the Kunlun series, which is an upgraded alternative to DZ47. It has a more modern design, better material technology, and some models have passed international certifications such as CE and TUV. At present, DZ47 has been partially discontinued, and NXB has become the mainstream choice.

II. Comparison of Core Technical Parameters

1. **Breaking Capacity**  

   Both meet the 6kA standard, but NXB has a better arc-extinguishing grid design (for example, the 12.7g arc-extinguishing grid is better than the 12.1g one of DZ47S), and the actual short-circuit response speed is faster.

2. **Tripping Characteristics**  

   DZ47 provides three types of tripping curves: B/C/D (Type B: 3-5In, Type C: 5-10In, Type D: 10-14In), which are suitable for different load types; NXB only provides C/D types, focusing on lighting and power loads, but the Type C curve has higher precision and a lower misoperation rate.

3. **Service Life and Reliability**  

   The mechanical life of DZ47 is 10,000 times, and the electrical life is 4,000 times; the mechanical life of NXB is increased to 20,000 times, and the electrical life is 10,000 times. It also adopts silver alloy contacts and a flame-retardant PC shell, which can withstand high temperatures up to 750°C, and its anti-aging performance is significantly enhanced.

 III. Structural Design and Expandability

1. **Appearance and Installation**  

   NXB adopts a widened handle and energy-storage closing design, which makes the operation feel smoother and supports contact status indication. Both support 35mm guide rail installation, but NXB is more compact in size, saving distribution box space.

2. **Accessory Functions**  

   NXB can be expanded with accessories such as alarm auxiliary contacts (AL-X1) and shunt release (SHT-X1) to realize remote control and fault alarm; DZ47 has weak accessory compatibility, and only basic auxiliary contacts are available.

3. **Differences in Leakage Protection Models**  

   The NXBLE series has an automatic leakage detection function every 108 minutes, and prompts through an alarm module when there is an abnormality; DZ47LE only has basic leakage protection, no self-inspection function, and the response speed is slightly slower.

IV. Application Scenarios and Purchase Suggestions

1. **Applicable Scenarios**  

   - **DZ47**: Suitable for ordinary residential lighting circuits with limited budgets and stable loads, or temporary electricity usage scenarios.  

   - **NXB**: Recommended for household main switches, high-power electrical appliances (such as air conditioners, water heaters), and places with high safety requirements (such as commercial lighting), especially suitable for users who need to be compatible with smart home systems.

2. **Purchase Notes**  

   - **Channel Differences**: The NXB versions on e-commerce platforms may have reduced material quality. It is recommended to give priority to products from physical channels or official flagship stores.  

   - **Model Matching**: High-end models such as NXB-63Z support 10kA breaking capacity. The corresponding specifications should be selected according to the actual load current (e.g., below 63A).

V. Price and Cost-Effectiveness

The price of a 16A single-pole DZ47 is about 10-15 yuan, and the same specification of NXB is about 15-20 yuan. The price difference is mainly reflected in material upgrades and function expansion. From the perspective of long-term use, NXB has higher cost-effectiveness due to its long service life and low maintenance cost, especially suitable for long-term investment scenarios.

 Summary

Through material upgrades, function expansion, and process optimization, the NXB series has comprehensively surpassed DZ47 in terms of safety, reliability, and expandability. If you pursue economy and practicality with simple loads, DZ47 can still meet basic needs; if you focus on electrical safety and long-term stability, NXB is a better choice. It is recommended to comprehensively consider according to specific application scenarios and budgets, and give priority to NXB as a new generation of power distribution protection solutions.

The following is a comparison of the appearance and size parameters of Chint's NXB series and DZ47 series, sorted out based on official data and actual measurement data, covering basic models and leakage protection models:

I. Size Parameters of Basic Models

1. **Chint NXB Series (Kunlun Series)**

- **Pole Width**:  

  Adopting a standard modular design, the width of each pole is **18mm**, compatible with internationally通用 guide rails.  

  - **1P**: 18mm wide × 78mm high × 65mm deep (including terminals)  

  - **2P**: 36mm wide × 78mm high × 65mm deep  

  - **3P**: 53mm wide × 78mm high × 65mm deep  

  - **4P**: 71mm wide × 78mm high × 65mm deep  

- **Installation Compatibility**:  

  Supports **TH35-7.5mm** guide rail installation. The installation hole spacing is the same as that of DZ47 (single-pole hole spacing is 48mm), and it can be directly replaced.  

  - **Optimized Design**: Through the streamlining of internal structure, the height is reduced by about 10% compared with DZ47, and the depth is reduced by 5mm, improving the space utilization of the distribution box.

2. **Chint DZ47 Series**

- **Pole Width**:  

  It is also **18mm per pole**, but the height and depth of different pole numbers are slightly larger than those of NXB.  

  - **1P**: 18mm wide × 80mm high × 70mm deep  

  - **2P**: 36mm wide × 145mm high × 70mm deep  

  - **3P**: 54mm wide × 177.8mm high × 70mm deep  

  - **4P**: 72mm wide × 177.8mm high × 70mm deep  

- **Installation Characteristics**:  

  The guide rail compatibility is the same as that of NXB, but some early models (such as DZ47-60) have an installation hole spacing of 50mm, so attention should be paid to the adaptability of the distribution box.

II. Size Differences in Leakage Protection Models

 1. **NXBLE Series (Leakage Protection Type)**

- **Pole Width Expansion**:  

  Due to the built-in leakage detection module, the width is increased by about 1 time:  

  - **1P+N**: 45mm wide × 94.5mm high × 76.8mm deep  

  - **2P**: 63mm wide × 94.5mm high × 76.8mm deep  

  - **3P+N**: 99mm wide × 94.5mm high × 76.8mm deep  

  - **4P**: 115mm wide × 94.5mm high × 76.8mm deep  

- **Function Integration**:  

  The leakage module and the circuit breaker are integrated in design, supporting automatic leakage detection every 108 minutes, and the volume is about 15% smaller than that of DZ47LE.

 2. **DZ47LE Series (Leakage Protection Type)**

- **Size Comparison**:  

  The leakage module is designed independently, and the volume is larger:  

  - **1P+N**: 54mm wide × 100mm high × 80mm deep  

  - **2P**: 72mm wide × 100mm high × 80mm deep  

  - **3P+N**: 125mm wide × 100mm high × 80mm deep  

  - **4P**: 142mm wide × 100mm high × 80mm deep  

- **Installation Restrictions**:  

  Some models (such as DZ47LE-63) need to occupy additional guide rail space, so caution should be exercised when the distribution box capacity is small.

 III. Key Size Comparison Table

 IV. Installation and Model Selection Suggestions

1. **Distribution Box Space Planning**:  

   - **NXB Series**: The 1P model can realize complete protection functions within a width of 18mm, suitable for compact distribution boxes (such as household terminal boxes).  

   - **DZ47 Series**: Models with 2P and above have a larger height and need to reserve more vertical space, suitable for industrial distribution cabinets or scenarios with sufficient space.

2. **Guide Rail Compatibility**:  

   Both support TH35-7.5mm guide rails, but due to the larger height of the 3P/4P models of DZ47, they may interfere with the side panels of the distribution box, so measurements should be taken in advance.

3. **Selection of Leakage Protection Models**:  

   - **NXBLE**: Suitable for smart home systems, with high integration and small size, recommended for household main leakage protection.  

   - **DZ47LE**: Suitable for commercial lighting systems sensitive to cost, but attention should be paid to the distribution box capacity.

 V. Notes

1. **Influence of Current Specifications**:  

   The width and depth of models with 63A and above (such as NXB-125G) will increase by about 20%, and the size needs to be confirmed separately.  

2. **Risks of Third-Party Channels**:  

   The sizes marked on some e-commerce platforms (such as 10×10×10mm) are obviously wrong. It is recommended to refer to the official manual or product label.  

3. **Replacement Compatibility**:  

   NXB can directly replace the 1P/2P models of DZ47, but for 3P/4P, it is necessary to check whether the height of the distribution box is sufficient.

Summary

Through structural optimization, the NXB series has significantly reduced its volume while maintaining standard modules, especially suitable for residential power distribution scenarios with limited space; the DZ47 series still has a certain market in industrial environments, but attention should be paid to its larger external size. Among the leakage protection models, the integrated design of NXBLE has more advantages, while DZ47LE is suitable for cost-sensitive projects. It is recommended to choose according to the specific installation environment and functional requirements, and give priority to referring to the 3D model diagrams or PDF manuals provided on Chint's official website to confirm details.