مفتاح السكين فيوز كور RT-3 (NT3) تيار مستمر 440 فولت

The application of the knife switch fuse core RT-3 (NT3) in a 440V DC (تيار مستمر 440 فولت) system requires analysis based on specific model parameters and technical requirements. The key information is summarized as follows:

1. Model Correspondence and Technical Parametersمرحل متوسط ​​من شينت JZX-22F/4Z(د) 24VDC

Relationship Between RT-3 and NT3:

RT-3 may refer to models RT16-3 or RT36-3. These fuses typically correspond to Siemens’ NT3 series (على سبيل المثال, RT16-3 NT3). The NT3 series fuses feature a blade-type contact design, suitable for AC 50Hz/60Hz systems, though some models explicitly indicate DC voltage compatibility.

Rated Voltage and Breaking Capacityسعر مرحلات الحمل الزائد الحراري من سلسلة Chint NXR:

على سبيل المثال, the rated voltage of Chint RT36-3 (NT3) fuse cores includes AC500V/DC440V, with a breaking capacity of up to 100kA. Mingrong RT16-3 NT3 fuse cores also support DC440V, with a breaking capacity of 100kA. This indicates that some models in the NT3 series can meet the short-circuit protection requirements of DC440V systems.

الميزات الهيكليةسعر قاطع الدائرة الكهربائية CHINT:

The fuse core uses pure silver or pure copper melt encapsulated in a high-strength porcelain tube, filled with quartz sand as an arc-extinguishing medium, offering high breaking capacity and fast-blowing characteristics.

2. Considerations for DC Applicationsسعر واقي التيار CHINT

Polarity and Arc Extinguishing Performance:

Arcs in DC circuits are more difficult to extinguish, so the fuse’s arc-extinguishing design must be suitable for DC. The NT3 series effectively suppresses DC arcs through optimized melt structure and quartz sand filling.

Matching Breaking Capacity:

The breaking capacity (على سبيل المثال, 100ال) must be selected based on the circuit’s expected short-circuit current to ensure reliable circuit interruption during DC faults.

3. Application Scenarios and Installation Requirements

مجالات التطبيق:

Suitable for DC440V industrial power distribution, new energy equipment (على سبيل المثال, photovoltaic combiner boxes), DC charging piles, and other scenarios as overload and short-circuit protection components.

Installation Conditions:

The ambient temperature range is typically -5°C to 40°C, with an altitude not exceeding 2000 متر, and must meet IP protection grade requirements.

4. North American Market and Certification

UL Certification:

Some NT3 series fuse cores may be UL-certified (على سبيل المثال, compliant with UL248 standards), but confirmation by specific model is required. على سبيل المثال, fuses from Shenzhen Maiweitong Electronics meet UL certification and can replace imported products.

Supplier Information:

Compatible models in North America can be purchased through agents (على سبيل المثال, BUSSMANN in the U.S.) or local distributors.

5. Alternative Models and Compatibility

النماذج المكافئة:

RT16-3 NT3 can be interchanged with Siemens NT3, Chint RT36-3, and other models, provided the rated current and voltage parameters are identical.

Selection Advice:

For strict DC440V matching, it is recommended to prioritize models explicitly marked with DC440V (على سبيل المثال, RT36-4 or RT16-3 NT3) and refer to the manufacturer’s technical documentation.

6. خاتمة

خاتمة:

Some models in the NT3 series fuses (على سبيل المثال, RT16-3 NT3) are suitable for DC440V systems, with a 100kA breaking capacity, meeting the protection requirements of industrial DC circuits.

احتياطات:

– Confirm that DC440V is explicitly stated in the parameter table of the specific model.

– Ensure the breaking capacity matches the circuit’s short-circuit current.

– North American users must verify UL certification and local suppliers.

When purchasing the knife switch fuse core RT-3 (NT3) تيار مستمر 440 فولت, strict checks must be conducted across multiple dimensions, including technical parameters, compliance, supplier qualifications, and compatibility, to avoid system failures or safety risks due to improper selection or procurement. The key considerations are as follows:

1. Precise Matching of Technical Parameters
2. Clarity of Rated Voltage (تيار مستمر 440 فولت)

– Ensure the fuse core model explicitly marks DC440V (على سبيل المثال, RT36-3 NT3 DC440V) to avoid misusing models that only support AC500V in DC systems.

– ملحوظة: Some manufacturers may grade DC voltages (على سبيل المثال, DC250V/DC440V); verify that the DC breaking capacity curve in the parameter table covers the 440V operating condition.

2. Matching Rated Current with Load

– Select the fuse core’s rated current (على سبيل المثال, 125أ, 160أ, 200أ) based on the circuit’s maximum operating current, with a 1.2–1.5 times overload margin (refer to IEC 60269 المعايير).

– For impact loads like motor starting, choose gR type (general purpose) or aM type (motor protection) fuse cores to avoid false tripping.

3. Critical Value of Breaking Capacity (Icn)

– يجب أن يكون أكبر من تيار الدائرة القصيرة المتوقع للدائرة (على سبيل المثال, 100ال), with reference to the system short-circuit calculation report. If the actual short-circuit current exceeds the fuse core’s breaking capacity (على سبيل المثال, only 50kA), explosions or fires may occur.

1. Certification and Compliance Verification
2. Domestic Market: Mandatory CCC Certification

– Domestic models (على سبيل المثال, Chint RT36-3, Mingrong RT16-3) must pass CCC certification and bear the certification mark on the product body or packaging. Reject “no-brand” or OEM products.

2. Export or International Projects: Regional Certification Adaptation

سوق أمريكا الشمالية: Requires UL 248-1/14 (فتيل) or CSA certification; confirm the model suffix includes “أول” (على سبيل المثال, RT16-3 NT3 UL).

السوق الأوروبية: Must comply with CE certification (following EN 60269 المعايير) and confirm RoHS environmental requirements.

Special Industries: Such as rail transit or marine applications, additional compliance with industry standards like EN 50155 or IEC 60092 مطلوب.

ثالثا. Supplier and Product Authenticity Verification

1. Prioritize Original Manufacturers or Authorized Agents

– Siemens NT3 series is recommended to be purchased through Siemens’ official channels; domestic brands (على سبيل المثال, شينت, Tianzheng) can be procured via their official websites to query authorized distributor lists and avoid counterfeits.

– Be cautious of low-priced “disassembled goods” or unmarked products, as these fuse cores may be aged or have degraded breaking capacity.

2. Verify Product Identification and Anti-Counterfeit Information

– Genuine fuse cores have clear markings on the housing: model, المعلمات المقدرة, certification marks, production date (على سبيل المثال, “RT36-3 NT3 DC440V 160A CCC 202504”).

– Some brands offer QR code anti-counterfeit verification (على سبيل المثال, Chint’s “Taijike” platform); ensure consistency with official website information.

1. Mechanical Compatibility and Installation Adaptation
2. Matching Knife Switch Base

– NT3 fuse cores correspond to No. 3 blade-type contacts; ensure the knife switch base is of NT3 specification (على سبيل المثال, Siemens 3RV1011, Chint NH3-3) to avoid poor contact or installation issues due to mismatched contact sizes (على سبيل المثال, NT2/NT4).

– Installation direction: The fuse core must be inserted vertically into the base to ensure tight contact; avoid horizontal installation, which may cause melt sagging.

2. التكيف مع الظروف البيئية

Temperature: Confirm the ambient temperature is within -5°C to 40°C; if exceeded, derate the current (على سبيل المثال, reduce rated current by 5% for every 10°C above 40°C).

Altitude: For altitudes >2000 متر, select high-altitude fuse cores (marked “high-altitude type”) or derate the current, as low air pressure reduces insulation strength.

1. Documentation and After-Sales Service
2. Request Complete Technical Documents

– Require suppliers to provide specification sheets (datasheet), CCC/UL certification reports, and factory test reports, with special attention to DC breaking capacity test data (على سبيل المثال, DC440V/100kA breaking waveforms).

– للمشتريات بالجملة, طلب تقارير اختبار النوع (على سبيل المثال, third-party reports issued by national testing centers).

2. After-Sales Guarantee and Return Policy

– Confirm whether the supplier provides a quality guarantee period (typically 1–2 years); free replacement is required for non-human-caused damage during normal use.

– Retain technical clauses in the purchase contract, specifying that the supplier must bear return costs and joint liability if the product does not meet DC440V requirements.

1. Alternative Models and Emergency Procurement
2. Cross-Brand Alternative Risk Control

– If the original model is out of stock, equivalent domestic models (على سبيل المثال, RT36-3 replacing NT3) can be selected, but ensure the following parameters are identical:

– الجهد المقنن (تيار مستمر 440 فولت), التصنيف الحالي, breaking capacity;

– Contact size (لا. 3 blade type), mounting hole spacing (على سبيل المثال, NT3 standard hole spacing is 85mm).

– Avoid using models marked “compatible with NT3” but without explicit DC parameters (على سبيل المثال, fuses only marked AC500V).

2. Rapid Verification for Emergency Procurement

– For temporary purchases, request suppliers to provide DC breaking test videos or third-party inspection screenshots of the same batch to ensure reliability in urgent situations.

ملخص: قائمة مراجعة قرار الشراء