TRANSFORMER NAMEPLATE RATING

Following are the minimum information and Data which to be shown on a transformer nameplate. The standards require the following information and data for transformers rated above 500 kVA.

• Name of manufacturer
• Serial number
• year of manufacture
• Number of phases
• kVA or MVA rating
• Frequency
• Voltage ratings.
• Tap voltages.
• Connection diagram.
• Cooling class
• Rated temperature in °C
• Polarity (for Single Phase Transformers)
• Phasor or vector diagram (For Polyphase or Three Phase Transformers)
• % impedance.
• Approximate mass or weight of the transformer
• Type of insulating liquid.
• Conductor material of each winding.
• Oil volume (of each transformer Container/Compartment)
• Instruction for Installation and Operation

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ABSOLUTE AND SECONDARY INSTRUMENTS

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