ETL-35K is a versatile multipurpose cable and substation test van with three-phase connection to electrical test objects.
ETL-35K system has a multitude of applications in electrical equipment testing and maintenance: testing cable insulation with DC (rectified) voltage up to 60 kV, measuring small leakage current of surge arrestors, high-voltage testing with AC voltage up to 100 kV at industrial frequency, underground utilities tracing, cable fault pre-location and pinpointing, and measuring capacitance and tan delta of various electrical objects at industrial frequency.
ETL-35K is fitted with a collection of traditional and modern safety mechanism providing comprehensive operator protection operator.
THREE-PHASE CONNECTION
ETL-35K features a three-phase connection method to the test objects and a phase switch on the operator panel for a specific phase selection.
Three-phase connection makes fault location quick, easy and safe – it enables phase comparative pre-location methods, yet does not require an operator switching the connection leads.
AC & DC TESTING
Van-based cable fault and test system ETL-35K allows to carry out withstand testing of cable insulation with DC (rectified) high voltage up to 60 kV and testing other electrical objects with AC voltage up to 100 kV at industrial frequency (f = 50 Hz).
MEASURING LEAKAGE CURRENT OF SURGE ARRESTERS
A microammeter included with the system allows testing surge arresters with DC (rectified) voltage up to 60 kV and measuring the leakage current with up to 0.01 mA significance.
FAULT PRE-LOCATION
Detachable digital time-domain reflectometer RIF-9 included with the system is used for determining the distance to faults in electrical power cables with all the main pre-location methods:
Low-voltage method
- TDR (time-domain reflectometry): low-resistance faults, open cable breaks, various impedance changes characterization (cable sleeves, branches, etc.), total cable length measurement (incl. on a drum or bundle) and cable shortening ratio measurement.
High-voltage methods
- ARC/ARC multi-shot (arc reflection method): high-resistance and unstable faults, minimal harmful effects on a cable.
- ICE (impulse current envelope method): high-resistance faults that cannot be converted to low-resistance by burning faulty insulation.
- DECAY (voltage wave oscillation method): faults with high breakdown voltage.
POWERFUL BURN UNIT
ETL-35K is equipped with a powerful burn unit with output voltage level switch, used to convert high-resistance cable faults to low-resistance ones, which allows to subsequently apply pre-location and/or pinpointing methods for precise fault localisation.
ETL-35K burn unit provides output current up to 6 A at up to 20 kV voltage or output current up to 15 A at up to 0.5 kV voltage.
SURGE WAVE GENERATOR WITH A SURGE LEVELS SWITCH
A surge wave generator with up to 2000 J surge energy is used for pinpointing cable faults with an acoustic method.
The generator is supplemented with a surge level switch allowing to select output voltage in the ranges of 0…8 / 0…16 / 0…32 kV, which delivers maximum possible energy of the surge pulses.
CABLE TRACING AND PINPOINTING FAULTS BY INDUCTION METHOD
Cable test van ETL-35K can optionally be supplied with LFG-200 low frequency generator providing up to 200 VA of output signal power.
Addition of the generator, turns ETL-35K into a powerful system for underground utilities tracing, their burial depth determination and cable faults pinpointing by the induction method.
DIELECTRIC DISSIPATION FACTOR MEASUREMENT
ETL-35K system can be equipped with an optional Tan Delta module for accurate measurement of capacitance and the dielectric dissipation factor at up to 10 kV voltage of industrial frequency.
Tan Delta measurement using cable test vans is most often used to assess the transformer insulators on the electrical substations.
SAFETY
All ETL-35K cable test vans are equipped with all-round operator safety systems consisting of the following modules and devices:
✓ Overvoltage and overcurrent protection.
✓ Overheating protection.
✓ Equipment and vehicle chassis protective earthing.
✓ Continuous grounding monitoring system.
✓ Emergency stop button.
✓ Automatic discharge device.
✓ Light and sound indication of high voltage.
✓ Vehicle high-voltage compartment door closure sensors.
✓ Safety ON/OFF keylock switch.
✓ Self-health and safety monitoring of high-voltage switches.
