Testing to assess the health of power transformers and to diagnose problems is of utmost importance to ensure the long-term and safe operation of these very expensive power assets.
With the Omicron CPC 100 Multi-Functional Primary Test System, power transformers and their ancillary components can be tested:
• Tap changer
• Connection leads
• Surge arrestors
The CPC 100 provides an easy and accurate (4-wire connection) winding resistance measurement. Automatic measurement for tapped windings (by using CP SB1 with the on load tap changer) speeds up the measurement.
The CPC 100 automatically discharges the inductive energy, which makes the measurement safe.
After switching off a transformer or after applying DC signals to a transformer, the core remains magnetized. This can cause problems for further diagnostic measurements or can lead to higher inrush currents.
By using the CP SB1 switch box the integrated algorithm in the test system completely demagnetizes the transformer core.
For measuring ratio and excitation current, the test system provides a 2 kV output, delivering 2500 VA. The test voltage is generated digitally and the current is automatically measured within the test system. This makes the measurement highly accurate, easy to set up, fast and safe.
For power / dissipation factor (PF / DF) measurement of power transformers and bushings, the test system is combined with the CP TD1. Measuring this factor over a broad frequency range – in addition to mains frequency – helps to better assess the insulation condition, for example detect whether the cellulose or the oil is contaminated by moisture.
Power transformer testing
• DC winding resistance up to 100 ADC
• Transformer demagnetization with CP SB1
• Dynamic load tap changer diagnostics (on load tap changer test) up to 100 ADC | optionally with CP SB1
• Transformer turns ratio (TTR) per tap up to 2 kVAC | including polarity and excitation current | IEC 61387-1 support for transformer with unconventional vector groups
• Automatically determination of the transformer’s vector group with CP SB1
• Leakage reactance / short circuit impedance up to 6 AAC
• Transformer, bushing: power / dissipation factor (tan δ) + insulation capacitance up to 12 kV, 300 mA | frequency from 15 Hz to 400 Hz | with CP TD1
• Insulating fluids: power / dissipation factor (tan δ) up to 12 kV, 300 mA | with CP TD1 and CP TC12
• Excitation current per tap up to 12 kV, 300 mA | with CP TD1
• Frequency response of stray losses (FRSL)
• Surge arrestors: leakage current and watt losses up to 12 kV, 300 mA | with CP TD1