Chint NS2-25/4-6.3A is a starter protection switch specifically designed for three-phase squirrel-cage induction motors. It integrates the functions of a disjoncteur and a thermal relay, providing overload protection, phase failure protection, protection contre les courts-circuits, and infrequent starting control.
Model Interpretation:
NS2: Code de série (N stands for Chint, S stands for Starter)
25: Frame current rating (25UN)
4-6.3UN: Rated current range of the trip unit (adjustable within 4-6.3A)
- Paramètres techniques de base
| Élément de paramètre | Spécification |
| Tension d'isolation nominale | 690V |
| Rated Working Voltage | AC 230/240V, 400/415V, 440V, 500V, 690V |
| Rated Frequency | 50/60HZ |
| Setting Current Range | 4~6.3A |
| Instantaneous Electromagnetic Trip Current | 78UN (environ 12 times the setting current) |
| Capacité de coupure de court-circuit | Icu=100kA, Ics=7.5kA (at AC400V) |
| Classe de protection | IP20 (front side) |
| Fréquence de fonctionnement | ≤30 times/hour |
| Applicable Ambient Temperature | -5℃~+40℃ |
| Poids | Approximately 313g |
III. Caractéristiques fonctionnelles
- Multiple Protection Functions
Protection contre les surcharges: Built-in bimetallic thermal element acts when the current exceeds the setting current for a certain period, preventing motor burnout due to overheating.
Phase Failure Protection: Detects the loss of any phase in the three-phase power supply and immediately cuts off the circuit to protect the motor.
Protection contre les courts-circuits: Instantaneous electromagnetic trip unit operates rapidly (≤100ms) when the current reaches 78A, preventing the expansion of short-circuit faults.
Fonction d'isolement: Can be used as an isolating switch to ensure maintenance safety.
- Control Functions
– Integrates start/stop button control with a compact structure.
– Supports 35mm standard DIN rail mounting for quick deployment.
– Optional accessories available: Undervoltage Trip (UV), Déclenchement de dérivation (SH), Auxiliary Contact (AE/AU), Fault Signal Contact (FA).
- Scénarios d'application
NS2-25/4-6.3A is suitable for:
– Protection and control of three-phase induction motors with a power of approximately 2.2kW (400V).
– Control of small and medium-sized motors in factories and workshops, comme les fans, pompes à eau, convoyeurs, compresseurs, and other equipment.
– Motor control cabinets in building automation systems.
– Can replace the traditional circuit breaker + thermal relay combination scheme, saving space and costs.
- Précautions d'utilisation
- Exigences d'installation
– Install vertically with an inclination angle ≤±5° to ensure reliable operation.
– The tightening torque for the terminal screws (M4) is 1.7N·m; avoid over-tightening to prevent thread damage.
– Recommended wire cross-sectional area: 1~6mm², wire stripping length: 10mm.
- Paramétrage
Setting Current: Should be adjusted to 1.05~1.1 times the motor’s rated current to ensure protection sensitivity and avoid false tripping.
– When the ambient temperature deviates significantly from 25℃, adjust the setting current according to the temperature compensation characteristic table.
- Operating Restrictions
– Do not operate beyond the rated voltage or frequency.
– The operating frequency shall not exceed 30 times/hour; frequent operation will shorten the service life.
– It is strictly prohibited to disassemble or replace parts with live electricity; the power supply must be cut off first and confirmed to be de-energized.
- Référence de sélection
To select the appropriate NS2 series product for your motor:
- First determine the motor’s rated current.
- Choose a model whose setting current range includes the motor’s rated current.
- Motor power reference: NS2-25/4-6.3A is suitable for motors with a power of approximately 2.2kW (400V).
- In systems with high-order harmonics such as inverter power supply, it is recommended to select the specification according to 1.3~1.9 times the motor’s rated current.
Résumé
Chint NS2-25/4-6.3A is a reliable-performance motor starter protection switch that integrates protection and control functions. It is particularly suitable for three-phase induction motors of around 2.2kW. Not only can it effectively protect motors from overload, phase failure, and short-circuit damage, but it also simplifies the design of control systems, making it an ideal choice in the field of industrial electrical control.
Contacteur,disjoncteur,onduleur solaire,compteur électrique,batteries solaires



















NH42-63-318x560.png)



