General:  S11-M. R Three Phase Enclosed Distribution Transformer with wound-core is applicable to 10kV, 6kV transmission and distribution system for distribution, power supply and lighting in industrial, agricultural, mineral and petrochemical fields. Compared with series S9, 30% of no-load loss and 70% of no-load current can be decreased averagely. It is remarkable in saving energy. In addition to, its noise level is in conformity to national environmental protection policy. Therefore, it is regarded as wonderful product both in energy saving and environmental protection.  Service condition:  Normal service condition:  Elevation height less than 1000m  Environmental temperature  Max. Temperature +40 0C Max. Daily average temperature: +30 0C Max. Annual average temperature +20 0C Min. Temperature -30 0C Operation environment outdoor Symmetry of multi-phase power source Feature:  Core is wound by silicon strip with lower loss. Enclosed structure is also called as R-shaped core. Core limb and yoke cross-section is close to a circle. It is impact, lower no-load loss and smaller current. Due to fully enclosed transformer, isolation between oil and air keeps insulation away from moisture, which lowers insulation aging and improves service life. The product is free from untanking before operation and is free from maintenance during operation. Owing to the corrugated plate used for cooling for S11-M. R. Series, oil volume is changed by adjustment and compensation through expansion and shrinkage of corrugated plate when the temperature of oil is changed.  Ordering Notes:  1. Rated capacity 2. Phase number 3. Frequency 4. Rated voltage (L. V. &H. V. ) 5. Tapping range 6. Vector group