The characteristics of SC (B) series of dry-type transformers can fully satisfy the above requirements so they are fit for different engineering projects.
1. SC (B) 9 series: heat resistant grade is Grade F; no-load loss is 10% lower than that of national standard; the on-load loss is 10% lower than that of national standard; the noise is 10-20 dB lower than that of national standard; the design life is 30 years.
2. SC (B) 10 series: heat resistant grade is Grade F or H; no-load loss is 20% lower than that of national standard; the on-load loss is 15% lower than that of national standard; the noise is 15-30 dB lower than that of national standard; the design life is 30 years.
Because of their unique performance, SC (B) series of dry-type transformers are fit for the power supply locations with highly strict requirements such as high rise, subway, airfield, hospital and petrochemical enterprises. And the requirements of safety performance of power supply system are stricter and stricter.
Functional Features
1. Beautiful appearance
The products are cast by adopting imported Grade H epoxy resin in the vacuum state (1～3mbar); With thin insulated packing structure, the coil surface is bright and beautiful without need for any surface treatment; and the products are elegant and tasty.
2. Excellent electric performance, outstanding overload capability
Externally encapsulated resin is imported Grade H epoxy resin, with excellent electric performance; and special winding structure is adopted to ensure that the resin is completely saturated into each corner of the coil, and the clearances are eliminated, and make sure that the partial discharge of each product leaving factory is less than 5 PC, heat conductivity of the resin with packing is good, design scheme of axial heat radiation duct is adopted for transformers of large capacity; the transformer can be running under 120-130% of the load within long period , and can be running under 150% of rated load in the case of forced air cooling.
3. Low loss and noise
It is one of the first symbolic energy-conserving products that have passed the certification of China Standard Certification Center. Based on the national standard GS / T10228 - 1997, the no-load loss of SCB10 series of transformers is reduced by 20 % and the on-load loss is reduced by 15%. As for the iron core, highly magnetic quality cold rolled silicon steel sheet is utilized and low flux density design scheme is adopted. It is joined with an inclination of 45, without punching or plate-drawing process. Heat contraction with iron core tying technique is adopted. The core surface is coated with special resin to prevent humidity and rust and the body-compression structure patent is also adopted, effectively reducing no-load loss and no-load current. With low flux density design, far away from the saturation point of the iron core flux density, the noise level is apparently better than GB 15 - 25dB.
4. High mechanical strength, good capability of resisting short circuit
Adopt high purity silicon micro-powder as packing. The heat expansion coefficient approaches copper wire(copper 16*10- 6 ／℃, resin with packing 23 * 10 - 6／℃), it can expand by heating and contract by cooling simultaneously with the copper wire. And adopt special winding process to eliminate the chap and rejection problems. The mechanical performance of the resin with packing is stronger; the tensile strength reaches up to 68MP; no phenomenon affecting the structure of the transformer will appear after the transformer bears the electric power of short circuit, therefore the capability of resisting short circuit is greatly increased.
5. Safety, environmental protection and maintenance-free, long life
Being encapsulated by damp-proof, salt mist-proof and fungus-proof resin (i.e. "Three Proofs"), they can be put into use without any desiccation, and no need to carry out core suspension repair of oil-immersed transformers. Maintenance is seldom or never needed until the service life ends. They have the ability of fire retarding and self-extinguishing, without emitting any toxic gas so they are environment friendly products. The service life is greatly prolonged by adopting low temperature rise (80-90K, lower than the 100K temperature rise standard of Grade F products) and it generally can reach up to 30 years
Technical Parameter
Standard: IEC60076-11:2004/GB/T 10228-1997/GB 6450-1986/JB/T 10088-2004
Capacity: 30-10000kVA
Voltage grade: 35kV and lower
Phase: Three-phase or single phase
Frequency: 50Hz or 60Hz
Coupling group: Dyn11, Yyn0 (or according to the requirements of the users)
Tapping scope: ±2*2.5% (or according to the requirements of the users)
Heat resistance grade: Grade H
Insulation level (Grade 10kV): power frequency voltage withstanding 35kV, lightning strike voltage 75kV
Insulation level (Grade 20kV): power frequency voltage withstanding 50kV, lightning strike voltage 125kV
Insulation level (Grade 35kV): power frequency voltage withstanding 70kV, lightning strike voltage 170kV
Cooling type: AN/AF
Normal use conditions (Altitude): no more than 1,000m
Normal use conditions (Ambient temperature): max. temperature is no more than 40℃
Normal use conditions (Relative humidity): can reach up to 100%
Note: Carry out special design according to the requirements of the users if normal conditions are exceeded.
Protective grade: IP20 or IP 23 (or according to the special requirements of the users)
Voltage regulating type: Non-excitation voltage regulating or on-load voltage regulating