Unlike dry-type transformers, oil-immersed units can handle higher voltage ratings and larger capacities due to the efficiency of liquid cooling. Models are available in sealed oil immersed transformers for minimal maintenance or breathing designs with conservators for extended oil management. Depending on application, customers can choose distribution oil immersed transformers for local networks or power-grade models for grid-level operations.
Main Features
- Efficient cooling system using high-grade mineral oil.
- Durable tank design for outdoor and indoor installations.
- High dielectric strength ensuring insulation reliability.
- Wide capacity range from small kVA ratings to multi-MVA systems.
- Multiple cooling classes including ONAN (natural), ONAF (forced air), and OFAF (forced oil).
- Customizable designs for industrial, commercial, and utility needs.
| 4.Technical Parameters of 10kV Class SH15-M Series Amorphous Alloy Oil-immersed Transformer | |||||||||||||||
| Rated Capacity (kVA) | Voltage Combination (KV) | Low voltage | Connecion group designation | Loss(kW) | No-load current (%) | Short- circuit mpedance (%) | Weight(Kg) | Overall Dimensions(mm) (Length L×Width B ×Height H) | Torque (Longitudinal/ Transverse) | ||||||
| No-load | Load(75℃) | Body Weight | oil weight | Total weight | |||||||||||
| 30 | 11 10.5 10 6.3 6 | 0.4 | Dyn11 | 0.033 | 0.600 | 1.7 1.3 1.2 1.1 1.0 0.9 0.7 0.7 0.7 0.5 0.5 0.5 | 4 | 240 | 80 | 410 | 920×600×980 | 400×550 | |||
| 50 | 0.043 | 0.870 | 310 | 110 | 510 | 950×620×1040 | 400×550 | ||||||||
| 63 | 0.050 | 1.040 | 350 | 125 | 570 | 990×670×1040 | 400×550 | ||||||||
| 80 | 0.060 | 1.250 | 410 | 135 | 630 | 1030×720×1040 | 400×660 | ||||||||
| 100 | 0.075 | 1.500 | 475 | 150 | 720 | 1060×770×1070 | 400×660 | ||||||||
| 125 | 0.085 | 1.800 | 550 | 170 | 830 | 1060×900×1070 | 400×660 | ||||||||
| 160 | 0.100 | 2.200 | 630 | 190 | 960 | 1060×930×1150 | 400×660 | ||||||||
| 200 | 0.120 | 2.620 | 670 | 210 | 1040 | 1110×930×1170 | 550×820 | ||||||||
| 250 | 0.140 | 3.050 | 750 | 240 | 1160 | 1180×1010×1180 | 550×820 | ||||||||
| 315 | 0.170 | 3.650 | 810 | 264 | 1240 | 1180×1010×1180 | 550×820 | ||||||||
| 400 | 0.200 | 4.300 | 860 | 290 | 1330 | 1200×1010×1180 | 550×820 | ||||||||
| 500 | 0.240 | 5.150 | 950 | 320 | 1460 | 1270×1160×1200 | 660×1070 | ||||||||
| 630 | 0.320 | 6.200 | 0.3 0.3 0.3 0.2 0.2 | 45 | 1120 | 380 | 1860 | 1450×1240×1330 | 820×1070 | ||||||
| 800 | 0.380 | 7.500 | 1340 | 410 | 2230 | 1520×1380×1460 | 820×1070 | ||||||||
| 1000 | 0.450 | 10.30 | 1620 | 540 | 2700 | 1720×1460×1510 | 820×1070 | ||||||||
| 7250 | 0.530 | 12.00 | 1900 | 640 | 3180 | 1780×1500×1690 | 820×1070 | ||||||||
| 1600 | 0.630 | 14.50 | 2560 | 680 | 4240 | 1880×1540×1970 | 820×1070 | ||||||||
| 2000 | 0.750 | 17.40 | 0.2 0.2 | 5 | 2900 | 980 | 4920 | 2080×1580×1970 | 820×1070 | ||||||
| 2500 | 0.900 | 20.20 | 3940 | 1160 | 6560 | 2350×1580×2020 | 820×1070 | ||||||||
| Note:High | voltage | tapping | range:±5%or2×2.5%;Frequency:50Hz;Insulation | level:L175AC35/L10AC5. | |||||||||||
Key Advantages
- Superior thermal management for heavy loads.
- Extended service life due to oil immersion reducing stress on windings.
- Flexible configurations – sealed, conservator, or hermetically sealed types.
- Cost-effective performance with reduced downtime.
- Proven safety through international certifications and testing.
Applications
Oil-immersed transformer equipment is widely used in:
- Utility substations for medium to high-voltage conversion.
- Industrial manufacturing plants requiring reliable energy supply.
- Renewable energy grids including solar and wind farms.
- Commercial complexes such as airports, malls, and hospitals.
- Infrastructure projects like railways, ports, and smart cities.
Installation & Maintenance
Installation steps:
- Place the transformer on a firm, vibration-free foundation.
- Verify oil level and quality before energizing.
- Connect HV/LV terminals securely and test grounding.
- Inspect the cooling system for leaks or obstructions.
Maintenance tips:
- Perform oil sampling to monitor dielectric strength every 12–18 months.
- Inspect gaskets, bushings, and seals regularly.
- Monitor temperature and load indicators to avoid overheating.
- Clean radiators and ensure free airflow for efficient cooling.
How to Select the Right Oil-immersed Transformer
- Load capacity – match kVA/MVA ratings with system demand.
- Cooling class – choose ONAN, ONAF, or OFAF based on load cycles.
- Voltage levels – ensure compatibility with primary and secondary grid requirements.
- Environmental factors – sealed models are better for humid or dusty areas.
- Compliance standards – IEC, ANSI, or local grid specifications.
- Manufacturer reputation – select a certified, experienced supplier.
FAQ
What is the difference between oil-immersed and dry-type transformers?
Oil-immersed models use mineral oil for cooling and insulation, while dry-type relies on air or resin.
How long does an oil-immersed transformer last?
With proper maintenance, it can operate for 20–30 years or more.
Can oil-immersed transformers be installed outdoors?
Yes, their robust tank design makes them suitable for outdoor substations.
Is oil testing necessary?
Yes, regular oil analysis ensures insulation strength and prevents breakdown.
What cooling options are available?
Options include ONAN (natural), ONAF (forced air), and OFAF (forced oil circulation).
