Surge tester

Data records

• Surge testing is applied to motors from fractional-horsepower sizes up to multi-megawatt generators and, with a low-impedance coil accessory that supplies a higher surge current, to low-impedance coils. Source: Megger product page, web page edition. Verified 2026-10-27. Record instr.surge-tester.applies-to
• Throughout a test sequence the instrument watches the applied voltage; on detecting an insulation weakness it stops the sequence by itself, warns the operator and reports the values present when it stopped. Source: Megger product page, web page edition. Verified 2026-10-27. Record instr.surge-tester.breakdown-protection
• A surge tester applies a fast-rising voltage pulse to a winding and examines the damped oscillation that follows; it is the method that exposes turn-to-turn insulation weakness, which the insulation tests made between winding and ground do not reveal. Source: Megger product page, web page edition. Verified 2026-10-27. Record instr.surge-tester.definition
• The surge test locates insulation weakness within a winding, between phases, between coils and in the groundwall; the analyzer also reports opens, high-resistance connections, phase imbalance and the effect of contamination on insulation strength. Source: Megger product page, web page edition. Verified 2026-10-27. Record instr.surge-tester.faults-found
• An optional partial discharge measurement made during the surge pulse detects discharge activity in the winding insulation and points to the locations of insulation stress. Source: Megger product page, web page edition. Verified 2026-10-27. Record instr.surge-tester.partial-discharge
• A static motor analyzer combines the surge test with winding resistance, insulation resistance, polarization index, dielectric absorption, step-voltage, ramp-voltage and hipot tests in one instrument, run as repeatable user-programmable sequences. Source: Megger product page, web page edition. Verified 2026-10-27. Record instr.surge-tester.static-test-suite
• Repeating an identical test sequence over the life of a motor and trending the results reveals the progression of insulation degradation, which supports predicting failure and planning replacement. Source: Megger product page, web page edition. Verified 2026-10-27. Record instr.surge-tester.trending
• Surge testers are used for quality assurance of rebuilt and newly manufactured motors before they enter service, in motor repair shops and in predictive maintenance programs. Source: Megger product page, web page edition. Verified 2026-10-27. Record instr.surge-tester.uses
• In the surge comparison test the oscillation recorded from each phase is overlaid on the others or on a reference from a known good winding; a weak turn insulation that arcs under the pulse shifts the waveform, and built-in software assists the comparison. Source: Megger product page, web page edition. Verified 2026-10-27. Record instr.surge-tester.waveform-comparison