Power plants typically use generator step-up (GSU) transformers, station service/auxiliary transformers, and unit auxiliary transformers in switchyards. The GSU increases generator output (e.g. 13-24 kV) to transmission voltages (110-400 kV), enabling efficient bulk power transfer. Auxiliary transformers supply plant loads such as pumps, fans, and control systems. These units must withstand high fault currents, thermal cycling, and fast switching events common in plant operation.

Star, delta, and zig-zag; vector groups define clock notation and phase displacement.

Major overhauls include extensive testing: DGA, furan analysis, oil dielectric strength, moisture content, insulation resistance, polarization index, winding resistance, TTR, sweep frequency response analysis (SFRA), and sometimes partial discharge tests. Bushings and OLTCs are inspected and tested separately. Thermal imaging may be used under controlled load. Results are compared to factory baselines and historical data to detect mechanical displacement, insulation aging, or emerging faults, informing decisions about refurbishment, uprating, or replacement.

The filtration capacity of TOR-5 is intentionally moderate, because it is designed for continuous conditioning, not bulk oil processing. In typical configurations, the circulation flow rate is on the order of 10-50 liters per hour, depending on the pump and cartridge set used. This low flow is sufficient to control moisture and contaminants over time without disturbing transformer hydraulics. TOR-5 is not meant to replace mobile oil treatment units, but to stabilize oil quality gradually during normal operation.

Field diagnostics include de-energized tests like insulation resistance, winding resistance, TTR, and DGA sampling, as well as energized tests such as infrared thermography, partial discharge monitoring, and acoustic analysis. Oil dielectric tests verify moisture and contamination levels. Results are trended against historical baselines to detect emerging issues like hot-spot degradation, cellulose aging, OLTC contact wear, and incipient faults.

Costs vary by kVA, voltage, and utility spec; small pole units may cost hundreds to several thousand USD, excluding installation and logistics.

Apparent power is the product of RMS voltage and current that defines transformer kVA/MVA rating. It sets thermal and insulation limits while real power depends on load power factor. Utilities specify transformers in kVA because power factor varies by user.

Image received. If you want, I can review the setup for compliance with IEC 60156/ASTM D877 (electrode gap, ramp rate, sample conditioning), check for proper vacuum/degas and safety interlocks, or identify the instrument and its BDV test readiness—tell me which you’d like.

Thank you for your follow-up. GlobeCore offers various transformer oil purification units for degassing, dehydration, and fine filtration. We will prepare a new quotation and ensure you receive all details promptly.

The TOR-1 is recommended for measuring dissolved water in transformer oil in ppm. Please confirm sample volume and accuracy requirements to issue a quotation.