Table of Contents
Overview of ONAN Transformers
ONAN transformers, or Oil Natural Air Natural transformers, are widely recognized for their efficiency and reliability in electrical power distribution. These transformers utilize oil as a cooling medium while relying on natural air for heat dissipation. This design allows them to operate effectively in various environmental conditions, making them suitable for both urban and rural settings.
The 1800 kVA ONAN transformer is particularly noteworthy, offering a robust solution for applications requiring substantial power capacity. With its high efficiency, it is an ideal choice for industries, commercial buildings, and large facilities looking to optimize their energy usage. The transformer’s ability to handle heavy loads without overheating is a major advantage.
Quality Manufacturing by Chinese Makers

China has emerged as a leading manufacturer of transformers, including the ONAN type. These manufacturers are known for their advanced production techniques and adherence to international quality standards. Many companies employ state-of-the-art technology to ensure that each transformer meets rigorous performance criteria, which is essential for the safety and reliability of power systems.
Among the key benefits of sourcing ONAN transformers from China is the competitive pricing without compromising quality. Many Chinese makers offer a range of options that cater to different specifications, ensuring that clients can find a transformer that fits their unique needs. Additionally, the manufacturing process often includes stringent testing phases to guarantee optimal performance.
| Type | Rated capacity (KVA) | No-load losses(W) | Voltage combination (KV) | Load losses(W) | No-load current (%) | Short-circuit impedance (%) |
| S11-M-30 | 30 | 100 | 6,6.3,10,10.5,11/0.4 | 600 | 2.3 | 4.0 |
| S11-M-50 | 50 | 130 | 6,6.3,10,10.5,11/0.4 | 870 | 2.0 | 4.0 |
| S11-M-63 | 63 | 150 | 6,6.3,10,10.5,11/0.4 | 1040 | 1.9 | 4.0 |
| S11-M-80 | 80 | 180 | 6,6.3,10,10.5,11/0.4 | 1250 | 1.9 | 4.0 |
| S11-M-100 | 100 | 200 | 6,6.3,10,10.5,11/0.4 | 1500 | 1.8 | 4.0 |
| S11-M-125 | 125 | 240 | 6,6.3,10,10.5,11/0.4 | 1800 | 1.7 | 4.0 |
| S11-M-160 | 160 | 280 | 6,6.3,10,10.5,11/0.4 | 2200 | 1.6 | 4.0 |
| S11-M-200 | 200 | 340 | 6,6.3,10,10.5,11/0.4 | 2600 | 1.5 | 4.0 |
| S11-M-250 | 250 | 400 | 6,6.3,10,10.5,11/0.4 | 3050 | 1.4 | 4.0 |
| S11-M-315 | 315 | 480 | 6,6.3,10,10.5,11/0.4 | 3650 | 1.4 | 4.0 |
| S11-M-400 | 400 | 570 | 6,6.3,10,10.5,11/0.4 | 4300 | 1.3 | 4.0 |
| S11-M-500 | 500 | 680 | 6,6.3,10,10.5,11/0.4 | 5100 | 1.2 | 4.0 |
| S11-M-630 | 630 | 810 | 6,6.3,10,10.5,11/0.4 | 6200 | 1.1 | 4.5 |
| S11-M-800 | 800 | 980 | 6,6.3,10,10.5,11/0.4 | 7500 | 1.0 | 4.5 |
| S11-M-1000 | 1000 | 1150 | 6,6.3,10,10.5,11/0.4 | 10300 | 1.0 | 4.5 |
| S11-M-1250 | 1250 | 1360 | 6,6.3,10,10.5,11/0.4 | 12800 | 0.9 | 4.5 |
| S11-M-1600 | 1600 | 1640 | 6,6.3,10,10.5,11/0.4 | 14500 | 0.8 | 4.5 |
| S11-M-2000 | 2000 | 2280 | 6,6.3,10,10.5,11/0.4 | 17820 | 0.6 | 5.0 |
| S11-M-2500 | 2500 | 2700 | 6,6.3,10,10.5,11/0.4 | 20700 | 0.6 | 5.0 |
| S11-M-30- | 30 | 90 | 20,22/0.4 | 660 | 2.1 | 5.5 |
| S11-M-50- | 50 | 130 | 20,22/0.4 | 960 | 2 | 5.5 |
| S11-M-63- | 63 | 150 | 20,22/0.4 | 1145 | 1.9 | 5.5 |
| S11-M-80- | 80 | 180 | 20,22/0.4 | 1370 | 1.8 | 5.5 |
| S11-M-100- | 100 | 200 | 20,22/0.4 | 1650 | 1.6 | 5.5 |
| S11-M-125- | 125 | 240 | 20,22/0.4 | 1980 | 1.5 | 5.5 |
| S11-M-160- | 160 | 290 | 20,22/0.4 | 2420 | 1.4 | 5.5 |
| S11-M-200- | 200 | 330 | 20,22/0.4 | 2860 | 1.3 | 5.5 |
| S11-M-250- | 250 | 400 | 20,22/0.4 | 3350 | 1.2 | 5.5 |
| S11-M-315- | 315 | 480 | 20,22/0.4 | 4010 | 1.1 | 5.5 |
| S11-M-400- | 400 | 570 | 20,22/0.4 | 4730 | 1 | 5.5 |
| S11-M-500 | 500 | 680 | 20,22/0.4 | 5660 | 1 | 5.5 |
| S11-M-630 | 630 | 810 | 20,22/0.4 | 6820 | 0.9 | 6 |
| S11-M-800 | 800 | 980 | 20,22/0.4 | 8250 | 1.8 | 6 |
| S11-M-1000 | 1000 | 1150 | 20,22/0.4 | 11330 | 0.7 | 6 |
| S11-M-1250 | 1250 | 1350 | 20,22/0.4 | 13200 | 0.7 | 6 |
| S11-M-1600 | 1600 | 1630 | 20,22/0.4 | 15950 | 0.6 | 6 |
Long Warranty Period for Peace of Mind
One of the standout features of ONAN transformers produced by reputable Chinese manufacturers is the long warranty period they typically offer. A prolonged warranty not only reflects the confidence these makers have in their products but also provides peace of mind for customers. It ensures that any potential issues can be addressed without incurring additional costs.
<pThe extended warranty periods can vary, but many manufacturers offer warranties of up to five years or more. This commitment to quality assurance is essential for businesses that rely heavily on uninterrupted power supply. Knowing that their investment is protected allows companies to focus on their core operations without the constant worry of equipment failure.
