Professional electrical equipment - generators, transformers, switchgear

Reliable Power Supply - Used Energy Equipment from Renowned Manufacturers

We specialize in the supply of used electrical equipment: power generators 10-3000 kVA, power transformers 100-40000 kVA, medium/low voltage switchgear, UPS systems, cogeneration units. We collaborate with brands such as Caterpillar, Cummins, ABB, Siemens, Schneider Electric. Each device undergoes a 195-point inspection including insulation tests, winding resistance measurements, load tests, transformer oil analysis, and thermal imaging of connections. Savings when purchasing used equipment amount to 40-60% while maintaining efficiency >95% and a lifespan of 15-25 years.

Key Parameters Verified Before Sale

We perform insulation resistance measurements (>100 MΩ at 5kV DC), dielectric strength tests (2×Un+1kV for 60s), winding resistance measurements (deviation <2% from factory), DGA analysis of transformer oil (dissolved gases

Main Categories of Equipment:

Power Generators: Caterpillar, Cummins, Perkins, MTU. 10-3000 kVA, soundproof enclosures, synchronization, ATS/AMF.

Transformers: ABB, Siemens, Schneider. Oil/Resin, 100-40000 kVA, 6-35/0.4 kV, Dyn11/Yyn0.

Medium Voltage Switchgear: ABB SafeRing/SafePlus, Siemens 8DJH, Schneider SM6. 12-24 kV, 630-2500A, 16-31.5 kA.

UPS Systems: APC, Eaton, Emerson. 10-800 kVA, online double conversion, autonomy 5-120 min, static bypass.

Advanced FAQ - Diagnostics and Operation of Energy Equipment

How to Conduct Comprehensive Diagnostics of a 1600 kVA Oil Transformer 15/0.4 kV Before Purchase?

External inspection and documentation: Tank condition: no penetrating corrosion, flexible seals. Insulators: no cracks, signs of surface discharges. Conservator: oil level 50-75%, breather operation. Radiators: unobstructed, no leaks, valves open. Nameplate: compliance of parameters with documentation. Buchholz: operation test, no gas in the relay. Thermometers: consistent readings, alarm contacts functional. Basic electrical measurements: Insulation resistance (megger 5kV DC): GN>1000 MΩ, DN>800 MΩ, GD>1500 MΩ @ 20°C. Absorption coefficient R60/R15: >1.3 (good condition). Polarization coefficient R600/R60: >1.5-2.0. Winding resistance: GN side: RAB, RBC, RCA difference <2%. DN side: Rab, Rbc, Rca difference <2%. Comparison with factory data: deviation <5%. Temperature corrected to 75°C for comparison. Transformation ratio and connection group: Measurement of transformation ratio: each tap switch position. Tolerance: ±0.5% from nameplate value. Connection group: verification of Dyn11 or other using a phase meter. Phase shift: compliant with group ±1°. Dielectric strength test: Test voltage GN: 38 kV AC/60s (for 15kV). Test voltage DN: 3 kV AC/60s (for 0.4kV). Between phases and to ground: no breakdowns or jumps. Leakage current: <50 μA, stable during the test. Transformer oil analysis (DGA): Hydrogen H2: <150 ppm (thermal/electrical breakdown). Methane CH4: <120 ppm (local overheating). Ethane C2H6: <65 ppm (oil overheating). Ethylene C2H4: <50 ppm (overheating >500°C). Acetylene C2H2: <5 ppm (arc discharges!). CO: <500 ppm, CO2: <5000 ppm (cellulose degradation). Physicochemical parameters of oil: Breakdown voltage: >60 kV/2.5mm (IEC 60156). Water content: <20 ppm for transformer in operation. Loss factor tgδ: <0.5% @ 90°C. Acidity: <0.1 mgKOH/g (fresh <0.03). Interphase voltage: >40 mN/m (new >45). Partial discharge (PD) measurement: PD level: <10 pC at 1.1×Un (good condition). PRPD pattern: no concentration in specific phases. Location: acoustic/electrical source of PD. Trend: stable during a 30-minute test. Additional measurements: Short-circuit impedance: 4-6% typical for 1600 kVA. No-load current: <2% of rated current. Losses: no-load <2.5 kW, load <17 kW @ 75°C. Tap switch test: fluidity, resistance <500 μΩ. Thermal imaging: Connections: ΔT<30°C at 80% load. Insulators: uniform temperature, no hot spots. Radiators: temperature gradient consistent with circulation. Bushings: no overheating at sealing points. Load test (if possible): 100% load for 4h: stability of temperatures. Noise: <65 dBA at 1m distance. Vibration: <100 μm on the tank at 50 Hz. Voltage regulation: ±5% range, smooth operation. Technical condition assessment: Very good condition: possible operation for 15-20 years. Good condition: 10-15 years with periodic maintenance. Satisfactory condition: 5-10 years, requires oil regeneration. Poor condition: major repair or replacement necessary. Required documentation: Factory protocols: FAT, nameplate data. Operating history: loads, failures, repairs. Recent tests: max 2 years, parameter trends. Certificates: compliance with standards, UDT approvals.