25kVA Conventional Type Single Phase Pole Mounted Transformer

Technical Specifications

25kVA Conventional Type Single Phase Pole Mounted Transformer

Technical Specifications

Customization Optional

25kVA Conventional Type Single Phase Pole Mounted Transformer

ZiSheng'S 25kVA Conventional Type Single Phase pole Mounted transformer can provide a variety of optional specifications according to different countries, grid standards and customer needs to adapt to different application scenarios and operating environments.
The high-voltage side can be selected from 2.4kV, 4.16kV, 7.2kV, 11kV, 13.2kV, 15kV, 19.92kV, 24.94kV, 33kV, etc. to meet the distribution voltage standards of different countries or regions. The low-voltage side can be selected from 120V/240V, 220V/240V, 277V/480V, etc., suitable for residential, commercial and industrial use. The adjustable tap can be selected from the NLTC (No Load Tap Changer): ±2 x 2.5% or ±5% voltage regulation range to adapt to voltage fluctuations.
The transformer insulation level is optional. According to ANSI, IEC or other international standards, common rated insulation levels include BIL (Basic Impulse Level) 30kV, 45kV, 60kV, 95kV, etc., which can be selected according to the lightning protection requirements of the power grid system. Enhanced insulation version suitable for high thunderstorm areas or high altitude environments.

The lightning arrester is installed on the high voltage side to prevent lightning strikes and operating overvoltage from damaging the transformer. The pressure relief valve prevents the oil tank from bursting due to excessive internal pressure, enhancing safety. Thermometer and Oil Level Indicator are used to monitor the transformer oil temperature and oil level in real time to prevent overheating or oil level drop. Gas Relay (for sealed transformers) detects gas generated by internal faults to improve safety. Low voltage circuit breaker (LV Circuit Breaker) provides short circuit protection and overload protection. Load break switch facilitates load switching and improves maintenance convenience.
ZiSheng'S 25kVA Conventional Type Single Phase pole Mounted transformer has optional specifications covering voltage level, insulation level, cooling method, transformer oil, protection device, housing protection, noise control, environmental adaptability, intelligent monitoring function, etc. Users can customize the most suitable transformer configuration according to specific grid requirements, operating environment and special needs to improve the safety, reliability and operating efficiency of the equipment.

Packing and Shipping

25kVA Conventional Type Single Phase Pole Mounted Transformer

ZiSheng To ensure that the 25kVA Conventional Type Single Phase pole Mounted transformer is intact during transportation and storage, the manufacturer will adopt strict packaging and transportation solutions to adapt to different logistics environments and the needs of the final installation site.
Use fully enclosed wooden cases for long-distance transportation or sea transportation to prevent external impact, rain and moisture. Vacuum sealed moisture-proof packaging is suitable for high humidity environments to prevent transformer oil from getting wet or metal parts from rusting.
Anti-seismic cushioning materials fill the packaging with foam, rubber pads or inflatable bags to reduce the impact of vibration and impact on the transformer.
Suitable for international export, usually 20-foot or 40-foot containers are used, and moisture-proof and anti-corrosion treatment is carried out in accordance with international shipping standards. Transformers may be packaged in a single wooden box or multiple transformers may be combined and fixed to maximize loading efficiency. The oil tank must be sealed to prevent moisture or temperature changes during sea transportation, which may cause oil quality deterioration.
The center of gravity is clearly marked on the outside of the transformer packaging to avoid tilting or tipping. Provide lifting hooks or lifting rings for safe handling by forklift or crane. During long-distance transportation, some customers may require the installation of vibration sensors or impact indicators to check for severe collisions upon arrival.
The packaging and transportation of ZiSheng'S 25kVA Conventional Type Single Phase pole Mounted transformer requires appropriate protective measures according to the specific transportation method and storage conditions to avoid physical damage, environmental factors and quality problems before installation. Manufacturers usually provide standard, reinforced and customized packaging, and ensure safe and reliable transportation, and finally deliver it to the customer site smoothly to ensure the normal operation of the transformer.

Manufacturer Test

25kVA Conventional Type Single Phase Pole Mounted Transformer

Progress Test

ZiSheng'S 25kVA Conventional Type Single Phase pole Mounted transformer during the manufacturing process, the quality of key materials such as silicon steel sheets, magnet wires, insulation materials, transformer oil, etc. is checked to ensure compliance with standards. Dielectric strength of insulation materials, oil quality analysis, thickness and coating of steel are tested. Winding resistance is measured to ensure the number of coil turns and wire specifications are correct. The insulation strength of the winding is tested to prevent short circuits or inter-turn faults. These tests ensure that the quality of the transformer meets IEC 60076, ANSI C57.12.20 or other international standards. Oil processing monitors dehydration, filtration cycles, and dielectric sampling to reach <10 ppm moisture and >50 kV breakdown strength. These incremental inspections allow early detection and correction of nonconformities, ensuring final product meets efficiency, impedance, and durability requirements.

Transformer Factory Acceptance Test

The Factory Acceptance Test (FAT) of ZiSheng'S 25kVA Conventional Type Single Phase pole Mounted transformer is designed to ensure that the transformer complies with the design specifications and international standards (such as IEC 60076, ANSI C57.12.20). The tests include key performance indicators such as winding resistance, dielectric withstand voltage, no-load and short-circuit losses, insulation resistance, etc. to verify the safety and reliability of the product. Oil quality analysis includes dielectric breakdown, moisture content, acidity, and dissipation factor per ASTM to confirm fluid suitability. Functional verification operates tap changer, fuses, arresters (if CSP), pressure relief device, and oil gauge. Optional witnessed tests may include sound level measurement or temperature rise heat run. Certified test reports with traceable calibration data and customer witness provisions (if requested) document all results, confirming the transformer meets efficiency, dielectric, and safety requirements for reliable overhead service.

Routine Test - Impulse Tests

Purpose of Testing

The purpose of Impulse Tests is to verify the insulation strength of electrical equipment when it is subjected to lightning strikes or switching overvoltages. By applying high-energy impulse voltages, it is possible to detect potential defects in the insulation system.

Testing Equipment

Impulse voltage generator (e.g. Haefely, Hipotronics, Tettex, etc.)
Voltage divider (used to measure impulse voltage waveform, resistor divider or capacitor divider)
Oscilloscope (used to record impulse waveform, common brands such as Tektronix, Keysight)

Pre-Test Preparation

Please test under suitable environmental conditions: relative humidity less than 65%, no rain or condensation (recommended temperature: 15-30°C).
Calibrate and check the impulse voltage generator, measurement system, and control system to ensure that the instruments and equipment are in good condition and meet the test standards.

Test Progress

Connect the Test Instrument:
Connect the impulse voltage generator correctly to each winding terminal (high voltage terminal, ground terminal) of the device under test, and ensure that all test instruments are well grounded.
Apply Test Voltage:
Select the appropriate impulse voltage waveform and amplitude according to the rated voltage of the equipment

Measure and Record

Collect and record the impact waveform, including:
Front Time
Time to Half-Value
Peak Voltage
Distortion
Ambient temperature and humidity (especially when the test environment needs to be corrected)

Waveform Correction

Check whether the impulse voltage waveform meets the specification requirements (wave head time 1.2μs ±30%, half-peak time 50μs ±20%).
If the waveform deviation is too large, adjust the impulse generator parameters and reapply the test.

Repeat Testing (if necessary)

Impact tests are performed for different phases and windings (HV/MV/LV).
In special cases, inter-winding impact, voltage-to-ground impact or coil corner impact are performed (according to the test plan).

Evaluation Criteria (Reference)

No internal insulation breakdown or flashover (detected by observing waveform continuity and audibly).
Waveforms are stable and meet standard specifications.
Waveform variations between repeated tests are minimal (usually good waveform overlap with no noticeable abnormal excursions).

*These comprehensive tests ensure that each transformer meets performance standards and operates reliably under various conditions.

Application

Widely used in suburban residential neighborhoods, rural homes, small farms, weekend cabins, and light commercial loads requiring dependable overhead step-down from medium-voltage distribution lines to 120/240 V single-phase service. Provides cost-effective, low-maintenance power for typical household and small-business consumption in utility overhead networks.