Common installation errors and risks of 10kV SC(B) Series Dry-type transformers

2025,05,20

Recently, many friends who have purchased dry-type transformers have been asking about the problem points that may occur during equipment installation. In this issue, Jutai will provide a detailed explanation of the common errors and risks of the 10kV SC(B) series dry-type transformers for everyone. We also welcome friends in need to visit our platform to consult product details. Don't miss out on high-quality transformer manufacturers.

1. Wrong wiring ‌

Winding in reverse or phase error ‌

If the beginning and end of the high-voltage or low-voltage side windings are connected in reverse, it will cause an imbalance in the three-phase current, local overheating of the windings, and in severe cases, insulation breakdown or burnout.

When multiple parallel wound coils are connected in series, the lead wires at the head and tail are confused, resulting in a reduction in the number of turns of the coils, an increase in the voltage per turn, and accelerating insulation aging.

The busbar is not properly connected ‌

Failure to apply conductive paste or insufficient bolt torque (such as M12 bolts not reaching the 45N·m standard) leads to an increase in contact resistance, causing overheating or even welding.

2. Installation environment and fixing issues ‌

Insufficient ventilation and moisture-proofing ‌

The humidity at the installation site was not ensured to be ≤85% (at 20℃), or dehumidification devices were not installed in high-humidity environments (such as tunnels and offshore platforms), resulting in moisture absorption of the epoxy resin layer and a decline in insulation performance.

Base FIXED NOT up to standard ‌

The horizontal error of the base is greater than 2mm/m, or it is not reinforced with welded or embedded bolts. Long-term vibration causes the clamping parts to loosen and the core to shift, increasing noise and magnetic leakage loss.

A grounding resistance greater than 4Ω may cause abnormal partial discharge or damage to the equipment during a lightning strike.

3. Heat DISSIPATION SYSTEM CONFIGURATION error ‌

Improper installation of FAN ‌

The axial flow fans were not evenly distributed according to the heat dissipation requirements, or the dust accumulated on the blades was not cleaned, resulting in a decrease in the efficiency of forced air cooling and a temperature rise exceeding the 100K threshold.

Temperature control debugging omission ‌

Failure to set the over-temperature alarm (130℃) and trip threshold (150℃), or failure to test the automatic start and stop function of the fan, may delay the handling of overheating faults.

4. Insulation and mechanical damage ‌

The coil surface bumped ‌

During handling, no special lifting gear was used or manual priing was carried out, resulting in cracking of the epoxy resin castable. The partial discharge was greater than 5pC, shortening the service life.

Core lamination process defect ‌

The 45° fully inclined joint five-step iron stacking process was not adopted, resulting in an increase of more than 10% in no-load loss and noise > 55dB.

5. Errors in commissioning and acceptance ‌

Critical test ‌ was not performed

The winding insulation resistance (hot air drying is required when < 100MΩ) or DC resistance (phase-to-phase deviation > 2%) was not measured, which may leave hidden defects.

The no-load test was not compared with the factory data (the deviation should be ≤±10%), and potential faults of the core or windings were ignored. ‌

Standardized installation should focus on avoiding wiring errors, improper environmental adaptation, heat dissipation failure and mechanical damage, and ensure the long-term stable operation of the equipment through strict acceptance tests (such as insulation resistance and temperature control function).

Author:

Mr. jiawenhan

E-mail:

JT13797437282@gmail.com

Phone/WhatsApp:

+86 13797437282