CHINT NS2-32H 17-23A AC motor starter

The following are the detailed technical parameters and application guidelines of the CHINT (CHNT) NS2-32H 17-23A AC motor starter, compiled by combining official documents and actual scenarios, covering key dimensions such as core functions, electrical performance, control characteristics, and compatibility:

1. Core Functions and Positioning

The NS2-32H belongs to a motor starter, which is mainly used for overload, phase failure, and short-circuit protection of three-phase asynchronous motors and for infrequent starting control. It is suitable for scenarios such as industrial equipment, pumps, and fans. Its core features include:

Setting current range of 17-23A: It is suitable for motors with a power of approximately 3kW (needs to be adjusted according to the actual load).

Tripping characteristics: It complies with the 10A class of the IEC 60947-2 standard and is suitable for loads with high starting currents (such as fans and water pumps).

Integrated protection function: There is no need for an additional thermal relay, simplifying the design of the control cabinet.

1. Electrical and Mechanical Parameters
2. Electrical Performance

2. Mechanical Specifications

Dimensions: 120×100×80mm (H×W×D), suitable for installation on a standard 35mm rail.

Weight: Approximately 0.8kg.

Protection level: IP20 (needs to be installed in the control cabinet).

Installation methods:

Front panel wiring: Connect the main circuit through screws (recommended).

Plug-in installation: Requires a special base (such as the CC series conversion connector, see).

III. Control and Interface Parameters

1. Control Functions

Manual/Automatic reset:

Manual reset: Press the reset button (RST) to restore after tripping.

Automatic reset: Switch by adjusting the screw (manual reset by default, see).

Test function: Supports simulated overload testing to verify the effectiveness of the protection function.

2. Interface Configuration

1. Environment and Certification

Operating temperature: -5°C to +40°C (without derating), and a 20% derating is required from +40°C to +60°C.

Altitude: No derating when ≤ 2000m, and derating is required when exceeding this altitude.

Certifications:

Domestic: CCC certification (see the certificate number).

International: CE certification (complying with EN 60947-2), and some models support UL certification (the specific model needs to be confirmed).

1. Typical Applications and Configuration Examples
2. Motor Protection Scenarios

Fan control:

Parameter setting: Set the setting current = motor nameplate current × 1.1 (considering the starting impact).

Cooperating equipment: Used in combination with CHINT NXC contactors (such as NXC-32), and simplify the wiring through the CC conversion connector (see).

Water pump control:

Function activation: Connect to the PLC through the auxiliary contacts to achieve fault alarm.

Special requirements: If the water pump starts and stops frequently, it is recommended to select the automatic reset mode.

2. Matching with Frequency Converters

Compatibility:

Current matching: The output current of the frequency converter needs to be ≤ the setting current of the NS2-32H.

Harmonic processing: If the frequency converter causes current distortion, the setting current needs to be increased by 1.3-1.9 times (see).

Installation suggestions:

Position: Install on the output side of the frequency converter, close to the motor.

Interference suppression: Use twisted-pair wires to connect the control circuit to avoid high-frequency interference.

1. Precautions and Selection Suggestions
2. Selection Key Points:

Current range: Select according to the rated current of the motor (17-23A is suitable for a 3kW motor).

Tripping grade: The 10A class is suitable for loads with long starting times (such as fans). If quick tripping is required, the 10 grade can be selected.

2. Installation Requirements:

Heat dissipation space: Reserve a 50mm gap at the top/bottom to avoid the influence of high temperature on the protection accuracy.

Wiring torque: Tighten the main circuit terminals to 4N·m to prevent poor contact.

3. Fault Troubleshooting:

False tripping: Check the motor load, whether the wiring is loose, or reduce the starting current.

No tripping: Test whether the protection function fails and replace the equipment if necessary.

VII. Accessories and Alternative Solutions

1. Optional Accessories

Auxiliary contact module: AX-6 (1NO + 1NC), used for remote monitoring of the fault status.

Conversion connector: CC-3(NS2), quickly connect the contactor and the starter (see).

Waterproof installation box: Improve the protection level to IP55, suitable for humid environments.

2. Alternative Models

Upgrade solution: If higher breaking capacity is required, the NS2-80H (80A, see) can be selected.

Economical choice: NS2-32 (without auxiliary contacts), with a cost reduction of approximately 30%.

The overload protection action time of the CHINT NS2-32H 17-23A thermal overload relay strictly follows the 10A class tripping curve of the IEC 60947-2 standard, and the matching of its core parameters with the actual application scenarios is as follows:

1. Core Parameters of the Overload Protection Action Time

According to the IEC 60947-2 standard and CHINT’s official technical documents, the action time characteristics of the NS2-32H are as follows:

1. Dynamic Characteristics in Practical Applications
2. Inverse Time Characteristic

The action time of the NS2-32H has a non-linear relationship with the overload current, specifically manifested as:

The larger the overload multiple, the shorter the action time. For example:

– When the current reaches 2 times the rated value (34-46A), the action time is approximately 30 seconds.

– When the current reaches 3 times the rated value (51-69A), the action time is shortened to 10 seconds.

Cold start characteristic: When overloading starts from a cold state, the action time will be slightly longer than that in a hot state (after running for a certain period of time), and the specific difference is approximately 10-15%.

2. Influence of Ambient Temperature

High-temperature environment (such as +50°C): The action time may be shortened by 20-30%, and the setting current needs to be appropriately reduced.

Low-temperature environment (such as -5°C): The action time may be extended by 10-15%, but it does not affect the effectiveness of the protection function.

3. Influence of Wiring and Installation

Too thin wires: An increase in the resistance of the connecting wires will cause the action time to be advanced. It is recommended to use multi-strand copper wires of 2.5mm² or above.

Poor heat dissipation: Insufficient installation spacing (such as the top/bottom gap < 50mm) will cause the action time to be shortened, and it is necessary to ensure good ventilation in the control cabinet.

III. Key Parameter Verification and Testing Methods

1. Manual Testing

Simulated overload: Raise the current to 1.5 times the setting current (25.5-34.5A) through an external voltage regulator, and observe whether the tripping time is ≤ 2 minutes.

Phase failure test: Disconnect any one-phase power supply and verify whether the tripping time is ≤ 2 seconds (phase failure protection characteristic).

2. Tool Verification

Clamp ammeter: Record the overload current waveform in conjunction with an oscilloscope, and confirm that the deviation of the action time from the theoretical value is ≤ ±10%.

Thermal relay tester: Special equipment such as CHNT-THR is recommended, which can accurately simulate the action time under different overload multiples.

1. Parameter Matching for Typical Application Scenarios

1. Precautions and Selection Suggestions
2. Cooperation with Contactors:

Recommended model: CHINT NXC-32 contactor (requires quick installation through the CC conversion connector).

Cooperation key points: The breaking capacity of the contactor needs to be ≥ the starting current of the motor (usually 6-8 times the rated current).

2. Alternative Solutions:

Upgraded model: If higher accuracy is required, the NS2-32H + AX-6 auxiliary contact module (supporting remote transmission of fault signals) can be selected.

Economical choice: If short-circuit protection is not required, it can be replaced with the NR2 series thermal relay (with a cost reduction of approximately 40%).

1. Typical Fault Troubleshooting