ETL-250
SUBSTATION EQUIPMENT TEST VAN
ETL-250 is a van-mounted system designed for testing electrical substation equipment.
Apart from insulation withstand testing with DC voltage up to 60 kV and ability to indicate very small leakage currents, the system can be used for testing various substation objects with small electrical capacitance with AC voltage of up to 250 kV and measuring tangent delta (dielectric dissipation factor) at industrial frequency.
DC TESTING
ETL-250 allows to carry out withstand testing of electrical insulation with DC (rectified) high voltage up to 60 kV.
AC TESTING
Van-based cable fault and test system ETL-250 includes high-voltage step-up transformer allowing to test various objects with small electrical capacitance with AC voltage up to 250 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.
DIELECTRIC DISSIPATION FACTOR MEASUREMENT
ETL-250 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 or up to 250 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.
| Connection | Number of phases | 1 |
| DC testing | Output current indication range | 0 … 60 kV |
| Output current indication range |
■ 0.01 … 3 mA, resolution 0.01 mA ■ 0 … 130 mA, resolution 0.1 mA |
|
| Indication | Digital indication of output voltage and current in real time | |
| Relative voltage and current indication error | ± 3 % of full range | |
| AC testing | Output voltage adjustment and indication range | 0 … 250 kV |
| Output current indication range | 0 … 70 mA | |
| Indication | Digital indication of output voltage and current in real time | |
| Relative voltage and current indication error | ± 3 % of full range | |
| Dielectric dissipation factor (Tangent Delta) measurement | Measured values |
■ Electrical capacitance ■ Tan δ ■ Operating voltage ■ Operating frequency |
| Measurement modes |
■ Direct ■ Inverted (optional) |
|
| Measurement voltage | up to 10 kV / 250kV | |
| Maximum load capacitance |
■ 64 nF @ 5 kV ■ 32 nF @ 10 kV ■ 890 nF @ 250 kV |
|
| Measurement error: | ||
| ■ Electrical capacitance | ± 5*10-2 % | |
| ■ Tan δ | ± (0.01*tan δ + 1*10-4) | |
| ■ Operating voltage | ± 1.5 % | |
| ■ Operating frequency | ± 0.1 Hz | |
| Safety | Isolation transformer | 30 kV•A |
| Grounding |
■ Protective earthing of the equipment and van chassis ■ Operating grounding ■ Vehicle chassis potential monitoring ■ Continuous grounding monitoring system ■ Automatic discharge device |
|
| Protection |
■ Overvoltage ■ Overcurrent ■ Overheating |
|
| High voltage presence signalling |
■ Light signalling (optional) ■ Acoustic signalling (optional) |
|
| High voltage switch off |
■ EMERGENCY STOP button ■ Power keylock switch ■ Open rear door monitoring |
|
| Power supply and consumption | Mains supply voltage | 230 VAC, ± 10 % |
| Mains supply frequency | 50 Hz | |
| Power consumption | up to 30 kV•A |
