Surge voltage testing

Surge voltage testing is used to discover insulation problems in wound materials. In studies, experts have determined that 60% of motor failures start out as coil shorts within a winding. A surge voltage test is the only testing method which can determine insulation problems in wound materials. In a surge voltage test, only the winding insulation against the earth/ground is tested.

In surge voltage testing, frequently called a surge test, a charged capacitor is switched very quickly in parallel to create a surge pulse in the windings to be tested. After connection, the stored energy in the capacitor is discharged into inductivity, then back into the capacitor, etc. Due to attenuation loss, this creates a sinusoidal dampened oscillation. This has a typical frequency, allowing the inductivity to be tested, as well as a characteristic amplitude curve. Changes in the winding parameters lead immediately to changes in the amplitude curve. The characteristics of the change are determined by the type and location of the problem. Glow discharges (corona) occur at weak areas which do not cause a flashover: Different assessment processes can be used to make problems visible and evaluate them.

A partial discharge test is often completed in addition to a surge voltage test, and hipot tests, resistance measurements, and tests of the direction of rotation are also often completed. As many connection points as desired can be tested using the integrated switching matrix.

You’ll always play it safe with devices by SPS electronic. SPS electronic offers a variety of solutions for surge voltage testing: Besides the portable ST 1800B (simple surge voltage testing device), our comprehensive product range also includes testing devices like the ST 3800L for OEM applications in systems.


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