What is a Varmeter?
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What is a Varmeter?
Varmeter Definition
A varmeter is defined as an instrument used to measure the reactive power in an electrical circuit.
Single Phase Varmeter
In single-phase varmeters, the pressure coil voltage leads the coil current by 90 degrees, and the reading represents the reactive power.
Polyphase Varmeter
Polyphase varmeters use two auto-transformers in an open delta configuration to create a phase shift for measuring reactive power.
Reactive Power Measurement
Reactive power is crucial to measure because high reactive power leads to a poor power factor and increased losses.
Harmonics Limitation
Single-phase varmeters may not measure reactive power accurately if harmonics are present in the circuit.
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