Series resonant test system

Data records

• Resonant test systems suit any load that is largely capacitive with low losses; variable-frequency systems are used first of all on gas-insulated switchgear and lines, and resonant systems in general on power cables, generator windings, capacitors and the dry testing of insulators. Source: Phenix Technologies product page, web page edition. Verified 2026-10-27. Record instr.series-resonant-test-system.applications
• When the test object flashes over, the circuit drops out of resonance and the test voltage collapses, so no transient overvoltage is generated at flashover. Source: Hipotronics product page, web page edition. Verified 2026-10-27. Record instr.series-resonant-test-system.flashover-behavior
• Variable-frequency resonant systems for on-site cable testing are built around series reactor modules carried on standard trailers, with the frequency converter and control cabinet housed in an air-conditioned container. Source: Haefely product page, web page edition. Verified 2026-10-27. Record instr.series-resonant-test-system.mobile-packaging
• A resonant set produces a pure sine wave with very low partial discharge of its own, so it serves as the voltage source for partial discharge measurement and for capacitance and tan delta bridges on cables, bushings and instrument transformers. Source: Hipotronics product page, web page edition. Verified 2026-10-27. Record instr.series-resonant-test-system.pd-and-tan-delta-source
• In a series resonant test system a high-voltage reactor is connected in series with the capacitive test object and the circuit is tuned to resonance at the test frequency, so that the inductive reactance of the reactor cancels the capacitive reactance of the test object and the supply has to provide only the losses of the circuit. Source: Electrical Testing Reference editorial taxonomy, 2026-10 edition. Verified 2026-10-27. Record instr.series-resonant-test-system.principle
• The quality factor Q of the resonant circuit is the ratio of the test voltage across the specimen to the voltage the feed transformer must supply, so a high Q means the feed transformer and its supply carry only a small fraction of the reactive power delivered to the test object. Source: Phenix Technologies product page, web page edition. Verified 2026-10-27. Record instr.series-resonant-test-system.q-factor
• Because the supply provides only the loss power, a resonant set is far lighter than a conventional test transformer set that would have to supply the whole charging current of the load, and the variable-frequency design has a much better power-to-weight ratio than a fixed-frequency resonant set. Source: Phenix Technologies product page, web page edition. Verified 2026-10-27. Record instr.series-resonant-test-system.size-advantage
• Resonance is reached either with a variable-inductance reactor whose core gap is moved at a fixed power frequency, or with a fixed reactor fed by a frequency converter that varies the frequency until resonance is found; the fixed-core variable-frequency design is lighter and more powerful for the same rating. Source: Haefely product page, web page edition. Verified 2026-10-27. Record instr.series-resonant-test-system.tuning-variants