Chint RT28N-32X fuse

The Chint RT28N-32X fuse is mainly designed for AC circuits, with its core parameters and application scenarios as follows:

I. Basic Specifications and Certifications

1. **Rated Parameters**  

   - **AC Voltage**: 500V AC, breaking capacity 100kA, rated current 32A, suitable for a fuse link with a size of 10×38mm.  

   - **Structural Design**: Adopts a cylindrical cap-type structure, supporting 1P/2P/3P pole configurations, and the base is designed with an indicator light (the suffix "X" in the model indicates it has a signal indicator).  

   - **Environmental Adaptability**: The operating temperature range is -5℃ to +40℃. No derating is required within an altitude of 2000 meters; beyond that, the current needs to be adjusted according to the correction factor.

2. **Certifications and Standards**  

   - Passed China's CCC certification (certificate number 2020980) and complies with the GB/T 13539.2-2015 standard.  

   - The breaking category is "gG", suitable for full-range overload and short-circuit protection.

 II. Limitations in DC Applications

1. **DC Compatibility**  

   - **Unclear DC Parameters**: The official data does not specify DC voltage levels (such as DC 1000V/1500V) and DC breaking capacity. It is designed based on the AC arc-extinguishing principle, and arc extinguishing is more difficult in DC scenarios.  

   - **Alternative Suggestions**: For DC application scenarios such as Chint photovoltaic combiner boxes, it is recommended to use special DC fuses (such as the NXK1 series) instead of the RT28 series.

 III. Installation and Purchase Suggestions

1. **Installation Method**  

   - Supports DIN 35mm rail mounting. The power supply must be cut off when replacing the fuse link to avoid the risk of electric shock.  

   - The base and the fuse link must be used together. For example, the RT28N-32X base is suitable for the RT28-32 type fuse link.

2. **Purchase Channels**  

   - **US Market**: Whatsapp: 0086-13811255435

 IV. Precautions

1. **Selection Risks**  

   - Forced use in DC circuits may lead to breaking failure. It is recommended to prioritize Chint's NHM5NEDC series DC isolating switches or special photovoltaic fuses.  

   - It is not recommended for special scenarios such as capacitor cabinets; it is suggested to replace it with the RT36 type.

2. **Technical Support**  

   - For DC applications, you can contact via Whatsapp: 0086-13811255435 to confirm customized solutions, or download the "RT28 Series Brochure" from the official website to obtain detailed parametersV. Typical Application Scenarios

- **AC Power Distribution**: Overload and short-circuit protection for industrial equipment and lighting systems.  

- **Conventional Circuits**: Basic protection for household distribution boxes and small control cabinets.  

- **Alternative Scenarios**: For DC protection, you can refer to Chint's photovoltaic combiner box solution, which has built-in dual protection of DC 1000V fuses and circuit breakers.

The RT28N-32X performs stably in AC scenarios, but its DC application needs to be carefully evaluated. It is recommended to select the appropriate model according to specific circuit parameters (voltage, current, breaking requirements) and give priority to referring to the manufacturer's technical documents or consulting professional engineers.

The dimensional specifications of the Chint RT28N-32X fuse need to distinguish between the **fuse link** and the **base component**, and attention should be paid to the differences in different pole numbers (1P/2P/3P). The following are detailed parameters based on official technical documents:

 I. Core Dimensional Parameters

1. **Fuse Link Dimensions**

- **Physical Specifications**: 10mm (diameter) × 38mm (length), suitable for standard 10×38mm cylindrical cap-type fuse links.

- **Structural Characteristics**: Ceramic shell with a metal cap, breaking capacity 100kA, rated current 32A.

2. **Base Component (Including Signal Indicator) Dimensions**

- **Relationship between Pole Number and Width**:  

  - **1P**: Width 17.5±0.5mm, height 74±1.5mm, depth 60±1.5mm, mounting hole diameter 10.3±0.2mm.  

  - **2P**: Width 35±1.0mm, other parameters are the same as 1P.  

  - **3P**: Width 52.5±1.5mm, other parameters are the same as 1P.  

- **Overall Height**: 38±0.6mm (including the indicator light module).  

- **Installation Method**: Supports DIN 35mm rail mounting, with a rail clamping width of 7.5mm, which can be fixed without additional tools.

3. **Installation Space and Weight**

- **Single Pole Weight**: 0.075kg (1P), 0.16kg (2P), 0.24kg (3P).  

- **Typical Installation Gap**: At least 5mm of heat dissipation space should be reserved for adjacent bases. It is recommended to install vertically in the distribution box for better heat dissipation.

 II. Key Design Details

1. **Signal Indicator Module**:  

   - The suffix "X" in the model indicates a built-in **LED indicator light**, which is integrated with the base in size, increasing by about 3mm in the height direction.  

   - Indicator Trigger Logic: When the fuse link blows, the internal micro switch closes, and the LED light turns on (requires external power supply support).

2. **Compatibility Design**:  

   - The base is compatible with **RT28-32 series fuse links** and similar international products (such as R015), but the rated current must be strictly matched.  

   - It is not compatible with fuse links of 14×51mm or 22×58mm specifications.

3. **Mounting Holes**:  

   - The back of the base is designed with **2 mounting holes**, with a hole spacing of 60±1.5mm (common for 1P/2P/3P), and the hole diameter is suitable for M4 bolts.  

   - No drilling is required for rail mounting; it can be directly clamped into the DIN 35mm rail, saving installation time.

III. Special Considerations for DC Applications

1. **Dimensional Adaptability**:  

   - If forced to use in DC circuits, attention should be paid to the risk of arc pulling due to **insufficient arc-extinguishing capacity**, but the dimensional parameters are exactly the same as in AC scenarios.  

   - Chint officially recommends prioritizing the **NXK1 series special DC fuses** (such as NXK1-1000V/32A) for DC scenarios, which have a size of 22×58mm and are suitable for larger bases.

2. **International Market Adaptation**:  

   - Users in the US market should note that the RT28N-32X has not passed UL certification, and the base width (17.5mm/1P) is compatible with some North American standard rails (such as TH35-7.5), but on-site measurement of the installation space is required.

IV. Selection and Installation Suggestions

1. **Pole Number Selection Logic**:  

   - **Single-phase Circuits**: 1P is sufficient to meet protection needs, saving space in the distribution box.  

   - **Three-phase Circuits**: The 3P base has a width of 52.5mm, and at least 60mm of horizontal space should be reserved.

2. **Comparison of Alternative Solutions**:  

   - For DC protection, it can be replaced with the **NHM5NEDC series DC isolating switch**, which has a size of 90×120×60mm and integrates the functions of a fuse and a circuit breaker.  

   - For special scenarios such as capacitor cabinets, it is recommended to use the **RT36-00 type fuse**, which has a size of 14×51mm and a higher breaking capacity (120kA).

3. **Installation Practical Points**:  

   - The power supply must be cut off before installation. A torque wrench should be used to tighten the bolts with a torque of 4N·m to avoid poor contact.  

   - The indicator module needs an external 24V or 220V power supply (the specific voltage depends on the model), and the terminal block is located on the side of the base.

V. Dimensional Adaptation for Typical Application Scenarios

- **Household Distribution Boxes**: The 1P base has a width of only 17.5mm and can be densely installed on standard DIN rails (such as 35mm wide), with a single row capable of accommodating more than 15 1P modules.  

- **Industrial Control Cabinets**: The 3P base occupies a width of 52.5mm. It is recommended to install it at least 20mm away from components such as contactors and relays for easy maintenance.  

- **Photovoltaic Combiner Boxes**: For DC protection, it is recommended to use the NXK1 series (22×58mm fuse link), whose base has a width of 36mm, adapting to the high-voltage requirements of photovoltaic systems.

In summary, the dimensional design of the RT28N-32X balances compactness and compatibility, but its DC application needs to be carefully evaluated. It is recommended to select the appropriate model according to the circuit topology (single-phase/three-phase), installation space, and breaking requirements, and give priority to referring to Chint's "RT28 Series Brochure".