Megger VLF CR-60HP Cosine Rectangular Wave Cable Withstand Voltage Test System
| Brand | Megger |
|---|---|
| Origin | United Kingdom |
| Model | VLF CR-60HP |
| Output Voltage | 0–60 kV RMS (VLF), 0–±60 kV DC |
| Frequency | 0.1 Hz |
| Max Capacitive Load | 6.5 µF @ 0.1 Hz / 60 kV RMS |
| Output Current | 0–17 mA (10 µA resolution) |
| Leakage Current Measurement | Integrated |
| Breakdown Detection | Real-time |
| Sheath Fault Location | 0–10 kV, Duty Cycle 1:3 / 1:5 / 1:9 |
| Input | 115 V / 230 V ±10%, 50/60 Hz, 1900 VA |
| Dimensions (W×H×D) | 1350 × 1250 × 1100 mm (1500 mm with rear access panel) |
| Weight | 380 kg |
| IP Rating | IP20 |
| Operating Temperature | –25 °C to +55 °C |
| Storage Temperature | –40 °C to +70 °C |
Overview
The Megger VLF CR-60HP Cosine Rectangular Wave Cable Withstand Voltage Test System is an engineered solution for diagnostic and commissioning testing of medium-voltage (MV) power cables rated up to 36 kV. It employs a 0.1 Hz very low frequency (VLF) cosine rectangular waveform—distinct from traditional sinusoidal or pure square wave outputs—to deliver high-energy stress while minimizing dielectric heating and avoiding polarization effects inherent in DC testing. This waveform meets the technical requirements of IEC 60502-2, IEEE 400.2, and VDE 0276 Part 1000 for field-based cable withstand verification. Designed for utility, industrial, and contractor applications, the CR-60HP enables reliable detection of insulation weaknesses—including water trees, voids, and partial discharge initiation sites—without imposing undue thermal or electrochemical stress on aged or moisture-affected XLPE or EPR cable systems.
Key Features
- High-energy 0.1 Hz VLF output with cosine rectangular waveform: maintains consistent peak voltage amplitude across full load range without frequency-dependent attenuation
- 60 kV RMS AC output capability supports testing of cables up to 20 km in length at rated capacitance (6.5 µF), enabling three-phase simultaneous evaluation
- Dual-mode operation: fully functional 0–±60 kV DC mode with polarity reversal for legacy acceptance testing and switchgear insulation assessment
- Real-time breakdown detection with sub-cycle response time, coupled with high-resolution leakage current measurement (10 µA resolution)
- Integrated sheath fault location module (0–10 kV, selectable duty cycles of 1:3, 1:5, or 1:9) for precise pinpointing of jacket damage in buried or ducted installations
- Onboard test logging with timestamped voltage, current, and time-domain waveforms; exportable via USB or Ethernet to comply with audit-ready documentation workflows
- Robust industrial enclosure (IP20) rated for field deployment in ambient temperatures from –25 °C to +55 °C
Sample Compatibility & Compliance
The VLF CR-60HP is validated for use with extruded dielectric cables including cross-linked polyethylene (XLPE), ethylene propylene rubber (EPR), and laminated paper-insulated lead-covered (PILC) designs. It conforms to international standards governing VLF withstand testing procedures, including IEC 60502-2 Annex G, IEEE Std 400.2-2013, and VDE 0276-620. Its waveform fidelity and measurement traceability support compliance with quality management frameworks such as ISO/IEC 17025 and regulatory expectations under utility asset integrity programs. While not a GLP/GMP instrument per se, its data logging architecture—including user authentication, electronic signatures, and immutable event timestamps—facilitates alignment with FDA 21 CFR Part 11 principles where required for critical infrastructure validation.
Software & Data Management
The system operates autonomously via its embedded control interface but integrates seamlessly with Megger’s optional PowerDB Pro software suite for centralized test planning, remote monitoring, and long-term trend analysis. All test records include raw waveform captures, leakage current profiles, pass/fail determinations per IEC-defined criteria, and operator metadata. Reports are generated in PDF and CSV formats, supporting direct import into CMMS platforms (e.g., SAP PM, IBM Maximo). Audit trails record configuration changes, calibration events, and user logins—ensuring full traceability during third-party inspections or regulatory audits.
Applications
- Post-installation commissioning of new MV cable circuits (up to 36 kV class)
- Periodic condition assessment of in-service underground and submarine cable networks
- Troubleshooting intermittent faults prior to excavation or replacement
- Verification of joint and termination integrity following repair or refurbishment
- DC withstand testing of cable terminations, bus ducts, and metal-clad switchgear
- Sheath integrity verification and fault location in single-core armored cables
FAQ
What standards does the VLF CR-60HP comply with for VLF testing?
It meets IEC 60502-2, IEEE 400.2, and VDE 0276-620 for waveform shape, voltage accuracy, and test duration requirements.
Can the system perform both VLF and DC tests on the same setup?
Yes—switching between 0.1 Hz cosine rectangular AC and ±60 kV DC modes is software-controlled and requires no hardware reconfiguration.
Is three-phase simultaneous testing supported?
Yes, with a maximum capacitive load of 6.5 µF at 60 kV RMS and 0.1 Hz, enabling full-circuit evaluation without phase isolation.
How is breakdown detected during a VLF test?
By continuous monitoring of instantaneous current slope and magnitude deviation exceeding user-defined thresholds, triggering immediate voltage ramp-down and event logging.
Does the unit include built-in reporting functionality?
Yes—test reports with waveform plots, leakage current trends, and pass/fail conclusions are generated onboard and exportable via USB or network interface.
