Chint Combined Switch NH5-20/4M04

Chint Combined Switch NH5-20/4M04 is a switching device suitable for low-voltage power distribution and motor control scenarios.
EU. Core Parameters and Structure
1. Significado do modelo
NH5: Chint isolation switch series, supporting high short-circuit breaking capacity and reliable isolation function.
20: Rated current of 20A, suitable for small and medium-sized load circuits.
4M04:
4P: 4-pole structure, capable of breaking three-phase live wires (L1, L2, L3) e fio neutro (N) simultaneously. It is applicable to three-phase four-wire systems and provides comprehensive circuit isolation and protection.
M04: Tripping type code, presumably a thermal-magnetic release, which has both overload long-time delay protection (thermal element) e proteção instantânea contra curto-circuito (electromagnetic element). It can realize two-stage protection without an external thermal relay.
2. Desempenho Elétrico
Tensão nominal: CA 400V (complying with NH5 series standards).
Quebrando Capacidade: With reference to the characteristics of the NH5 series, the short-circuit breaking capacity is presumably 12Ie/1s (ou seja, 240A short-time withstand current), which can handle sudden short-circuit faults.
Função de isolamento: Complying with GB/T 14048.3 padrão, it is equipped with clearly visible breaking contacts to ensure maintenance safety.
II. Cenários de aplicação
1. Power Distribution System
– Serving as the main switch of the terminal distribution box, it breaks the three-phase four-wire power supply and protects the lower-level circuits from overload and short-circuit damage.
– Suitable for power distribution systems of industrial equipment, commercial buildings, and residences, such as Motor Control Centers (MCC) and lighting distribution boxes.
2. Motor Control
– Directly controlling three-phase asynchronous motors with power ≤5.5kW (calculated based on the 20A rated current) to realize start-stop, commutation, and overload protection.
– When combined with contatores and thermal relays, it can form a complete motor control circuit to meet the needs of frequent operations.
3. Special Requirements
– The 4-pole design supports neutral wire protection, making it suitable for scenarios with three-phase unbalanced loads or harmonic interference (such as data centers and frequency conversion equipment) to prevent potential safety hazards caused by excessive neutral wire current.
III. Instalação e fiação
1. Método de instalação
– Standard 35mm guide rail installation, compatible with DIN EN 60715 padrão, saving space and facilitating maintenance.
2. Wiring Requirements
Incoming Terminal: Connect to three-phase power supply (L1, L2, L3) e fio neutro (N).
Outgoing Terminal: Connect to loads (such as motors and lighting equipment).
– Ensure firm wiring to avoid heating or poor contact caused by loose connections.
4. Certification and Reliability
1. Certification Standards
– Complying with GB/T 14048.3 (Low-Voltage Switchgear and Controlgear) e CEI 60947-3 international standards, and has passed CCC certification to ensure product quality and safety.
2. Adaptabilidade Ambiental
– Operating temperature range: -5℃ ~ +40℃, adaptable to most industrial and civil environments.
– Protection class: IP20 (preventing the intrusion of solid foreign objects larger than 12mm), and it needs to be used with a distribution box to improve protection performance.
V. Seleção de modelos e soluções alternativas
1. Comparison with Similar Products
Chint HZ5 Series: Both are combined switches, but the NH5 series has higher breaking capacity and is suitable for scenarios with stricter requirements for short-circuit protection.
Schneider NSX Series: If higher breaking capacity (por exemplo, above 50kA) or intelligent tripping function (electronic release) é necessário, upgrading to Schneider products can be considered, but the cost will increase significantly.
2. Recommendations for Alternative Models
– If a higher rated current (por exemplo, 63UM) is needed, NH5-63/4M04 can be selected; if a smaller current (por exemplo, 10UM) is needed, NH5-10/4M04 can be selected.
– For motor control, it can be matched with Chint CJX2 series contactors and JR36 series thermal relays to achieve more accurate protection.
Vi. Precauções
1. Load Matching
– Ensure that the load current does not exceed 20A. Especially when the motor starts, the instantaneous inrush current (geralmente 5-7 vezes a corrente nominal) should be considered to avoid false tripping.
2. Maintenance and Inspection
– Regularly check the wear of contacts. If ablation or poor contact is found, the switch should be replaced in a timely manner.
– The operating characteristics of the thermal-magnetic release are affected by the ambient temperature; long-term use in high-temperature environments should be avoided.
3. Installation Specifications
– Conduct wiring in strict accordance with the instruction manual to avoid reverse connection of live wires and neutral wires or short circuits.
– The neutral terminal of the 4-pole switch must be reliably connected and must not be left floating.
VII. Preço e Aquisição
Preço de referência: According to the market situation, the unit price of NH5-20/4M04 is approximately 150-200 RMB. For specific quotations, please contact via WhatsApp: 0086-13811255435.
Resumo
Chint Combined Switch NH5-20/4M04 is a cost-effective 4-pole isolation switch that integrates overload protection, proteção contra curto-circuito, and circuit isolation functions. It is suitable for small and medium-sized power distribution and motor control scenarios. Its thermal-magnetic release and 4-pole design provide reliable safety guarantees for three-phase four-wire systems, making it an ideal choice for industrial and civil fields. Ao selecionar o modelo, comprehensive consideration should be given to the actual load requirements and installation environment, and electrical installation specifications should be followed to ensure the stable operation of the system.