Winding inter turn impulse withstand voltage tester

Winding inter turn impulse withstand voltage tester(hereinafter referred to as the interturn meter) is suitable for rated voltage1140VInsulation testing of winding turns for micro motors, small power motors, and small and medium-sized motors (DC motors) below and below; It can also be used for inter turn insulation detection of transformer windings and electrical coils. Due to the inconsistent winding insulation structure and insulation materials of motor and transformer products from various production enterprises, especially the differences in process levels, improper operation in winding, wire embedding, wire scraping, joint, end shaping, handling and other process links can affect the insulation performance of the motor, resulting in various inter turn insulation hazards in the winding. Therefore, inter turn insulation of the winding is a key link in motors and transformers.

In order to improve the insulation testing level of motors and transformers, the United StatesNEMA. MG1-12.04And our national standardsGB755-2008 "Quota and Performance of Rotating Electrical Machines" andGB14711-2013 "General Safety Requirements for Small and Medium sized Rotating Electrical Machines" and GB/T22719.1—200Standards such as "Test Method for Interturn Insulation of AC Low Voltage Motor Loose Embedded Winding" have requirements and regulations.

Winding inter turn impulse withstand voltage testerIt is based on the theory of symmetrical balance of impedance of the test object, and uses the impulse ratio method to conduct non-destructive insulation simulation tests of equivalent overvoltage on the winding with high-frequency and high-voltage pulses. The waveform is recorded or observed using an oscilloscope configured with the instrument, and then compared and analyzed for stability. It can intuitively, quickly, and correctly detect and judge winding turn to turn short circuits and various impedance imbalance hazards.

Winding inter turn impulse withstand voltage tester Can detect potential hazards in the following windings:

• Interturn insulation breakdown (interturn short circuit)

• corona discharge

• Winding breakage

Winding inter turn impulse withstand voltage testerCompared with other similar products in the market, it has the following characteristics and functions:

• In order to ensure the accuracy of the test, the high-voltage pulse main circuit of the interturn instrument adopts a single high-voltage circuit switching output to ensure the symmetry of the interturn instrument itself;

• In order to improve the reliability and stability of the inter turn instrument operation test, a digital universal oscilloscope produced by a professional oscilloscope factory was used;

• It has the function of switching between forward and reverse tests, eliminating the unbalanced factors of impulse voltage applied to the winding and improving the level of insulation testing;

• Single phase motors and AC motors are universal, expanding the scope of application of the instrument.

Winding inter turn impulse withstand voltage testerWidely applicable to production enterprises, repair departments, scientific research and testing units of AC/DC motors, transformers, and electrical coils, it is a testing instrument that improves the level of inter turn insulation testing for products.

IIIWinding inter turn impulse withstand voltage testerMain technical parameters

• power supply220V±5%，50Hz±2%；500VA；

• Test voltage: 0.3～6kVContinuously adjustable within the range of p;

• Shock wave frequency:25Hz(Other frequencies can also be provided);

• Pulse capacitor:0.1mF(Other capacities to be negotiated separately);

• High output energy: 1.8J；

• Insulation resistance: The insulation resistance of the power input terminal to non electrified metal shell components is ≥20MOh?

• Dielectric strength: The power input terminal can withstand non electrified metal shell components1500V/50Hz, lasting for 1minThe withstand voltage test showed no arcing or breakdown phenomenon;

• Ambient temperature0～40℃；

9. Relative humidity: ≤80%；

10.Style: desktop;

11.Overall dimensions(mm)：648×520×335；

12.Quality: 50kg

13.Scope of application: Suitable for rated voltage1140V and 500kW and below motors.

4Winding inter turn impulse withstand voltage testerSimple working principle

The principle of the interturn meter is shown in the block diagram of Figure 1, and the circuit consists of an oscilloscope and a host system.

Working process: The circuit is mainly divided into two paths, one for preheating the oscilloscope and thyristor filament; The other route is controlled by a delay circuit.

Preheat the thyristor filament for about 8 hours firstminWhen the thyristor is controlled by the pulse signal triggering unit, the high-voltage device system is connected. Charging the pulse energy storage capacitor through high-voltage rectification, the thyristor is controlled by the pulse signal triggering unit to form a high-voltage pulse, which is then passed through the current limiting resistor to the electronic selection switch（“A—B”，“B—C”， “C-A”）， Then, by selecting "forward test" or "reverse test", it is sent to the test output terminal. High voltage pulses are alternately applied to the two test output terminals of the sample, and discharge generates attenuated oscillation waves. After being sent to the oscilloscope through the sampling circuit, the oscilloscope automatically synchronizes and tracks to display the signal waveform clearly and stably. The insulation performance between turns of the winding is judged by comparing the coincidence of the two impulse waveforms

5、 Names of switches and control buttons

Figure 2 Front panel diagram

Figure 3 Rear panel diagram

Note: For the control function and position of the oscilloscope switch, please refer to the attached oscilloscope manual.