2500kVA 13.8kV Pad-Mounted Fully Sealed Transformer

I.Pressure

Q1: What is the internal pressure of a pad-mounted transformer? Can it explode?

A: Pad-mounted transformers are of hermetically sealed construction. Under normal operating conditions, the internal pressure is very low (approximately 0.03–0.06 MPa). A pressure relief valve is installed on the top of the tank. If an internal fault causes a sudden pressure rise, the valve automatically opens to release pressure and then resets and re-seals after the pressure drops. Explosions will not occur. This is a standard safety feature of pad-mounted transformers.

Q2: Can it explode?

A: No. The unit is equipped with a pressure relief valve that automatically releases pressure in the event of overpressure.

Q3: What should I do if the pressure relief valve has operated?

A: Operation of the pressure relief valve indicates that an internal arcing fault or severe overload has occurred. Immediate investigation is required.

Q4: How can I check if the pressure relief valve is functioning properly?

A: Perform a visual inspection for oil leakage or signs of operation, and manually test the reset function.

Q5: How often should the pressure relief valve be replaced?

A: Inspect after every operation. Replacement is recommended every 10 years.

II.Oil Consumption

Q1: How can I tell if the oil has deteriorated?

A: Perform Dissolved Gas Analysis (DGA) — oil chromatography analysis — annually to detect characteristic fault gases.

Q2: What type of oil is used and how often should it be replaced?

A: We use Class II mineral oil or FR3 natural ester (vegetable) oil.

Replacement interval: Under normal use, replacement is not required for 10–15 years. Annual DGA testing is sufficient. If the oil fails testing (e.g., reduced breakdown voltage, excessive fault gas levels), oil filtration or replacement is necessary.

Q3: Does the oil evaporate? Is periodic oil top-up required?

A: No. The pad-mounted transformer features a hermetically sealed design, completely isolating the insulating oil from external air. Oil evaporation is virtually zero. Under normal conditions, no oil top-up is needed for 20 years. The oil level will only drop if a leak occurs, in which case the leak must be located and repaired before adding oil.

Q4: Is there a high risk of oil leaks in pad-mounted transformers?

A: Attention should be paid. Since the transformer tank is exposed to the outside, regular inspections should be carried out to prevent leakage caused by external mechanical damage. Selecting a stainless steel tank shell with enhanced protection can reduce the risk.

III.After-Sales Service

Q1: How long is the product warranty period? From which date does it start?

A: The warranty period is 2 years. It commences from the date of equipment acceptance. If acceptance is delayed for customer-related reasons, the warranty is deemed to start no later than 18 months from the date of shipment.

Q2: What after-sales service is available for overseas customers? Do you have overseas service centers?

A: We offer two service modes: remote video guidance and on-site service. Authorized service partners are available in key markets (e.g., Southeast Asia, Middle East). For other regions, we can dispatch engineers for overseas service (costs to be negotiated separately).

Q3: Who is responsible if the equipment is damaged during transit? How are claims handled?

A: Our factory is responsible for handling quality issues arising during transportation and will bear the associated costs.

Q4: How are quality issues during the warranty period handled? Is repair or replacement free of charge?

A: For issues caused by manufacturing defects, our factory provides free-of-charge repair. We also provide lifetime service and spare parts availability.

Q5: Can you provide installation and commissioning guidance?

A: Yes, we can.

IV.Delivery Lead Time

Q1: How soon can you ship after an order is placed?

A: Typically 15–20 days.

Q2: What is the delivery time for large-volume orders?

A: Depends on the quantity, generally 30–60 days.

Q3: Can you expedite an order? What is the expediting fee?

A: Yes. Urgent orders can be prioritized through production scheduling. Delivery time can be shortened to 7–10 days. The expediting fee is generally 10%–20% of the contract value, depending on the production schedule.

Q4: What is the delivery time for customized products?

A: Generally 30–45 days (e.g., special voltage, stainless steel tank, FR3 oil, etc.).

Q5: What packaging standards do you use? What level of moisture and rust protection is provided? Is it suitable for long-distance ocean freight?

A: Packaging complies with international standards. Moisture and rust protection levels reach IP33–IP56 with 20-year corrosion resistance. The hermetically sealed structure is highly suitable for long-distance ocean freight and has been successfully exported to numerous countries.

V.Spare Parts

Q1: Where can I purchase spare parts?

A: Spare parts can be sourced directly from our factory or locally.

Q2: What information is needed to order spare parts?

A: Serial number, photo of the nameplate, and the spare part name/model number.

VI.Other Frequently Asked Question？

Q1: What is the service life of a pad-mounted transformer?

A: Under normal operating conditions, the design life is 20–30 years. With its hermetically sealed, maintenance-free design, combined with regular inspections and annual DGA testing, stable operation for over 20 years is the standard expectation.

Q2: Are 50Hz and 60Hz transformers interchangeable?

A: Absolutely not!

Q3: Can you provide a spare parts list with part numbers?

A: Yes, we can.

Q4: If spare parts are not available locally, can you ship them directly overseas?

A: Yes, we can ship spare parts directly from our factory to your overseas location.