Dielectric test sets from Megger are designed to measure leakage current while applying a DC voltage at or above the insulation system’s operating level.
The test equipment helps to determine the insulation system’s ability to withstand over-voltage from lightning strikes or switching surges.
Megger portable DC dielectric test sets are used to assess the electrical insulation quality of motors, power cables, switchgear, insulators, transformers and capacitors.
Typical applications include acceptance and maintenance testing of critical equipment used by electrical utility substations and industrial plant distribution systems.
Power apparatus manufacturers may also use the equipment to perform QA/QC production tests.
The portable dielectric test sets can be used to perform step-voltage and proof tests which, when incorporated into a routine maintenance program can aid in predicting potential failure before breakdown occurs.
Dielectric test sets from Megger are available in two models: a 5 kV unit for testing equipment rated 2.5 kV and below as well as a 15 kV model for use on equipment rated 7.5 kV and below.
Both dielectric test sets are suitable for testing power cables, switchgear and rotating machinery in accordance with IEEE, ICEA, NEMA and ANSI guidelines.
Since Megger DC dielectric test sets act like full-wave rectified units, they are also suitable for applications involving vacuum bottles.
DC Vs. AC High-Potential Testing
Direct current high-potential testing provides several advantages over alternating current.
Direct current test equipment uses far less power, provides fast charging of highly capacitive test samples, can be easily transported to the test site and costs less than AC test equipment.
Additionally, the DC test equipment can detect incipient breakdown without the possibility of damage to good insulation.
- Compact and portable
- Air insulated, uses no oil
- ±2% accuracy
- Leakage current measurement as low as 0.1 mA
- Continuously variable test voltage with zero-start safety interlock
- Fast charging of high-capacitance samples
- Current guard circuit for highly accurate measurements
- Strip chart recorder for hard copies (optional)
- Rugged field construction
- Input and output line circuit breaker
- Output current overload relay
- Zero-start interlock for high-voltage output
- Switch control and indicating lights for high-voltage ON/OFF function on the 15 kV model
- Full circuit breaker protection