Product Details

Working Principle:

    The high-voltage test transformer is a single-phase transformer with connection group label I.I. It uses a 220V (380V for above 10KVA) power supply to connect to the series operation box (table). Through the auto-transformer voltage regulator inside the operation box (external for above 50KVA), the voltage is adjusted to 0-200V (or 0-400V) and output to the primary winding of the test transformer. According to the principle of electromagnetic induction, the power frequency withstand voltage test device can obtain the required high voltage for testing on the test transformer winding.

Supporting Products

1. Operating System:

Operation Box: Capacity: 1KVA-5KVA, Input Voltage: 0.22KV

Operation Table: Capacity: 10K/A-300KVA, Input Voltage: 0.22KV, 0.38KV

2. Protective Digital Microammeter SWB-Ⅱ

3. Resistive-Capacitive AC/DC Voltage Divider FYQ-50, 100, 150, 220KV

4. High-Voltage DC Discharge Rod FZ-70, 140, 210KV

5. High-Voltage Silicon Stack: 2DL-150, 300, 450KV

6. Insulation Support 50, 100, 200, 300KV

7. High-Voltage Filter Capacitor 0.01UF, 40-100KV

8. Corona Ring

9. Protective Sphere Gap: Q-50, 100, 150, 200, 250, 500

10. Standard Oil Test Cup 400ml

11. Dielectric Oil Cup

12. Folding Trolley 150, 300 Type

13. Water Resistor

14. High-Voltage Voltage Detector 10KV, 35KV

15. High-Voltage Phase Detector 10KV, 35KV/110KV, 220KV

16. Various Multimeters, Megohmmeters and Test Leads

Product Features:

◆ The product adopts a one-time pressed high-voltage bushing

◆ The bushing is completely isolated from the oil tank, and all connecting parts are sealed with imported oil-resistant O-rings, thoroughly solving the common problem of transformer oil leakage

◆ Horizontal core design effectively improves the product's seismic resistance

◆ All products undergo a 24-hour inverted test before leaving the factory to check for oil leakage in the test transformer

◆ All products can pass 1.1 times induced voltage withstand test

◆ Insulating oil uses colorless transparent Karamay original oil

◆ High and low voltage wires use high-strength polyester, oxygen-free copper rod enameled wire 

◆ The core uses brand new WISCO two-silicon cold-rolled silicon steel sheets

Capacity Selection:

The formula for determining the standard test transformer capacity Pn: Pn=KVn2ωct×10-9.

Where: Pn—Nominal test transformer capacity (KVA)

      Vn—Effective value of the rated output high voltage of the test transformer (KV)

      K—Safety factor. K≥1, when nominal voltage Vn≥1MV, K=2, when nominal voltage is lower, K value can be taken higher,

      ct—Capacitance of the test object (PF)

      ω—Angular frequency, 2лf. F - frequency of the test power supply.

The capacitance ct of the device under test can be measured by an AC bridge. Ct varies greatly and can be determined by the type of equipment. Typical data are as follows:

Simple rod or suspension insulators          tens of microfarads

Simple graded bushings                    100-1000PF

Voltage transformers                        200-500PF

Voltage transformers <1000KVA                -1000PF

                                  >1000KVA                 1000-10000PF

High-voltage power cables and oil-impregnated paper insulation          250-300PF/m

Gas insulation                              -60PF/m

Enclosed substations, SF6 gas insulation             100-10000PF

For different test voltages Vn, choose different (appropriate) safety factors K. The following lists the K values selected for different Vn for reference.

Vn=50-100KV       K=4      Vn=150-300KV      K=3   Vn>300KV           K=2



Overview:

The power frequency AC withstand voltage test complete device is produced based on the Ministry of Machinery and Electronics "Test Transformer" standard, after extensive improvements on the basis of similar original products. This series of products has the characteristics of small size, light weight, compact structure, complete functions, strong universality and convenient use. It is especially suitable for power systems, industrial and mining enterprises, scientific research departments, etc. to conduct insulation strength tests under power frequency or DC high voltage on various high-voltage electrical equipment, electrical components, and insulating materials. It is an indispensable important equipment in high-voltage testing.