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MCCB長時間熱校正ベンチ
IEC 60947-2 に準拠した過負荷試験用のカスタム MCCB 長時間熱校正ベンチ。高安定電流 (<2% drift), 4‑16 independent stations, programmable 100% / 135% In, automated data logging. Optional auto‑adjustment. Ideal for MCCB production QC and type testing.
High‑Stability MCCB Long‑Time Thermal Calibration Test Bench
これ MCCB長時間熱校正ベンチ is an essential solution for verifying and adjusting the thermal trip characteristics of molded case circuit breakers. Designed for continuous, high‑current operation (up to 500A or higher per station), it accurately simulates real‑world overload conditions, allowing manufacturers to calibrate the breaker’s trip curve for optimal overload protection. The system integrates high‑stability current sources (drift <2% over 8 hours), precise temperature monitoring, and automated data logging for full traceability.
Key capabilities include programmable test currents (e.g., 100% In, 135% In), multiple independent test stations, and real‑time trip time measurement with ±0.1% accuracy. The bench supports MCCB frames from 100A to 800A (customizable up to 1600A) and 1P‑4P configurations. An optional environmental chamber maintains consistent ambient temperature for even more repeatable results. All test results are automatically recorded and can be exported to MES for quality audits. Ideal for MCCB manufacturing QC, certification labs, and routine production sampling.
Standard delivery: 45-60 days | Current stability <2% drift | Multi‑station parallel testing
What is an MCCB Long‑Time Thermal Calibration Bench?
1 MCCB long‑time thermal calibration bench is a specialized test system used to verify and adjust the overload (thermal) trip characteristic of molded case circuit breakers. The thermal trip unit uses a bimetal strip that bends under prolonged overcurrent. This bench applies stable, programmable test currents (e.g., 100% of rated current to ensure no trip, then 135% to verify trip within the required time window) and measures trip time with high accuracy. Unlike simple go/no‑go testers, it also allows operators to adjust the bimetal position via a screw mechanism, re‑test, and confirm correct calibration. The bench typically includes multiple independent test positions, a high‑stability constant current source, and data logging software. It is essential for IEC 60947‑2 compliance (clause on overload protection) and is used in MCCB manufacturing plants, quality control labs, and certification bodies. As a non‑standard custom solution, we tailor the bench to your MCCB frame sizes, current ratings, and production volume.
Drift <2% over 8 hours, THD <3%, accuracy ±1% of reading.
Test multiple MCCBs simultaneously (4‑16 positions) for high throughput.
100%, 135%, 150%, or custom values per IEC 60947‑2.
Records trip time, test current, ambient temperature, and pass/fail status.
Key Features & Calibration Process
技術仕様
| Supported MCCB frames | 100A – 800A (standard); custom up to 1600A — |
|---|---|
| 試験ステーションの数 | 4, 8, 12, or 16 independent positions (customizable)— |
| Test current range | Up to 500A per station (expandable)— |
| 現在の精度 | ±1% of reading, stability <2% drift over 8 hours— |
| Timing resolution | 0.01s (standard), accuracy ±0.1% of reading— |
| テストの種類 | No‑trip at 100% In, trip at 135% In (or 150% In by IEC 60947‑2)— |
| Data logging | Trip time, test current, ambient temperature, pass/fail per station— |
| Cooling system | Forced air cooling between tests to ensure repeatability— |
| 制御システム | PLC (Siemens/Mitsubishi) with HMI, recipe storage for 20+ product types— |
| 電源 | 380V ±10% 50Hz | Three‑phase, heavy‑duty— |
主要な技術的利点
Exceptionally stable current over long tests
The bench’s closed‑loop current control (IGBT or thyristor) maintains set current within ±2% even after 8 hours of continuous operation – critical for long‑time tests that can last 1‑8 hours. Waveform distortion below 3% ensures accurate bimetal heating.
Parallel testing maximizes throughput
With 8 independent stations, you can calibrate 8 MCCBs simultaneously. Each station has its own current source, timer, and pass/fail indication. Bottlenecks are eliminated, and per‑unit test time is drastically reduced.
Automatic trip detection & adjustment assistance
Sensors detect the exact moment the breaker trips. The HMI displays trip time and compares it to the acceptable window. For adjustable breakers, we can integrate a stepper motor to automatically turn the calibration screw – forming a fully automatic calibration loop.
Temperature compensation for consistent results
Ambient temperature affects bimetal trip time. The bench monitors temperature and can automatically adjust acceptance windows or test currents to compensate. An optional environmental chamber maintains 25°C ±3°C for lab‑grade tests.
Customer Success Story – MCCB Manufacturer
A Brazilian MCCB manufacturer was experiencing inconsistent long‑time trip results due to unstable test currents. Their old bench had current drift >5% over 1 hour, causing false failures and rework. Benlong replaced it with an 8‑station long‑time thermal calibration bench featuring closed‑loop current control (<1% drift over 8 hours). Results after 3 months:
The bench paid for itself in 8 months and helped the customer pass an IEC audit with complete traceability records.
アプリケーションと統合
Custom Engineering & Delivery
Request a Custom MCCB Long‑Time Calibration Bench Quote
Send us your MCCB specifications (frame sizes, rated currents, test volume). Our engineers will design a bench with the optimal number of stations, current range, and data logging features – including a full ROI analysis.
WhatsApp: +86 150 5837 0007 | Email: xsb@benlongkj.cn | English & Chinese support
Why Choose Benlong for MCCB Calibration Benches?
- 15年以上のデザイン経験 thermal calibration equipment MCCBメーカー向け
- Proven high‑stability current sources (drift <2% over 8 hours)
- Multi‑station parallel testing (4‑16 positions)
- Integrated temperature monitoring and optional environmental chamber
- Full data logging with MES connectivity (OPC UA / Modbus)
一般的なカスタムベンチには以下が含まれます
High‑stability constant current source · Multi‑station test rack (custom positions) · Programmable current controller · Digital timers (±0.1%) · HMI touch screen · Ambient temperature sensor · Data logging software (CSV / SQL) · Forced cooling fans · Safety interlocks · Calibration certificate · 1‑year warranty
よくある質問
Long‑time thermal testing applies moderate overload currents (e.g., 135% In) for seconds to hours to verify the bimetal’s thermal trip characteristic. Instantaneous magnetic testing applies high currents (5‑10× In) for milliseconds to verify short‑circuit protection. This bench is dedicated to long‑time thermal tests only.
Standard configurations support 4, 8, 12, or 16 independent stations. Each station has its own current source and timer, allowing parallel testing of multiple breakers with different ratings.
The bench uses a closed‑loop current control system with a high‑accuracy current transformer and thyristor or IGBT regulator. It compensates for line voltage fluctuations and temperature drift, maintaining set current within ±2% over 8 hours.
Yes. For MCCBs with an external adjustment screw, we can integrate a stepper motor or electric screwdriver on each station. The system will test, adjust, and re‑test until the trip time falls within the acceptance window – fully automatic calibration.
At 100% In, the test runs for 1 hour (no trip expected). At 135% In, trip time is typically between 45‑55 seconds for a 100A frame. The bench can be programmed to run these sequences automatically.
