HCTT 150KV/20KVA Test Transformer

Mode: HCTT 150KV/20KVA
Cylinder type                                   HV current: 0.133A
Single phase                                     Cooling methods: ONAN
Frequency: 50Hz                             No-load current ≤10%
Rated Capacity: 20kVA                   Waveform deviation ≤5%
HV winding: 150kV                         Impedance voltage ≤10%
PD Level: <5pC at 100%UH of complete test system

Over-current capability: Working for 180s allowed at 120%In, not cause any damage to transformer winding and insulation.
Over-voltage capability: Working for 60s allowed at 110% rated current, not cause any damage to transformer insulation.
Insulation level: withstand 3kV/min (Low voltage input ending to ground)
Working time: half hour on, one hour off, eight cycles per day; and temperature rise of transformer winding is less than 65K, temperature rise of oil surface is less than 55K.

Transformer Oil: 
25# transformer oil is from Karamay Refinery. The oil indicator can reach the oil level for 500KV transformers. Factory test of test transformer should use new transformer oil supplying with transformers and perform oil inspection before or after factory test. Oil inspection report should be provided when the transformer delivered filled with oil. Quality of transformer oil should meet the requirements of SH0040-91, GB2536-90, GB7595-87, SD187-86, Class II A of IEC-296 standards. Components PCB are prohibited in the oil. When doing acceptance test on-site, the oil performance should satisfy the following requirements: DGA analysis of total hydrocarbons less than 10 mg/L, the breakdown voltage of the oil should not be less than 65kV/2.5mm, dielectric loss (90°C) is not more than 0.3%, water content is not more than 10mg/L, the gas content is not more than 1%.    

Principle Diagram: