Main specifications:

Main applications and characteristics:
These series are suitable for many applications, for example, (1）Heat treatment of gear and shaft（2）Various materials to be heated for shaping  （3）Copper contact brazing  （4）melting  
Due to the adopting of our third generation inverting control technology, These machines are characterized not only with high power and high frequency , but also with high reliability on the condition of normal IGBT module.

Advantages and applications of models with Timer function:
1. Heating power, retaining power, heating time, retaining time   can be preset and adjusted, this makes it possible to control the heating curve and heating time.
2. It is suitable to use in the repeated heating or high speed heating of small parts;
3. When using in brazing, with proper timing parameters, rapid heating and retaining can be achieved to keep the temperature while the brazing material is melted and then to let the brazing material spread smoothly to form good joint.

Advantages and applications of separated transformer:
1. In these three series machines, the high frequency transformer is separated from the generator, with 2 meters connecting cable at least.
2. It is suitable to use in the dirty or corrosive surroundings, the generator can be put in a clean space to increase the reliability.
3. With the small size and light weight of the separated transformer, it is convenient to use in the production line and easily assembled inside the machinery or moved mechanism.

Working theory and structure
In These series machines, series oscillating circuit is applied, through high frequency transformer, low voltage and high current power is output to go through the induction coil. The main oscillating structure is as follows:

      Inside These series machines, IGBT module and our third generation inverting control technology has been used, that is the soft and dual control and inverting technology. In this technology, output power and frequency can be controlled and adjusted separately, IGBT module and soft switching control technology are used in the high frequency switching circuit to control the output power.  In the inverting circuit, the IGBT and frequency tracing circuit is applied to achieve high speed and accurate soft switching control. The adoption of new technologies not only improves the quality and reliability of the machine，but also solve the technology problem on large power induction heating machine and makes it possible to work 100% duty cycle.
      Inside the These series machines, oscillating cap is connected to the secondary coil of the transformer, so the voltage on the primary coil of the transformer is low and problems caused by high voltage such as sparks and insulations are solved thoroughly to increase the reliability and quality of the machine. At the same time, the transformer is light and small sized with low energy consuming.

Comparison between SPG50K and  SP series machines:
1. Both SPG50K and SP have the same frequency range，but SPG50K has more advantages than SP；
2. Maximum current through coil:  Current through coil of SPG50K machines is obviously larger than that of SP machines of same power model. For example:  maximum current of SPG50K-25B is 1350A and 900A for SP-25BD in comparison.  Larger current is much better when heating copper, aluminium or other low induction load applications. For example, in brazing copper parts, SPG50K-25B is much quicker than SP-25BD.
3. Feature on High frequency:   Working frequency of SP machines is recommended around 50KHZ, when frequency is over 60KHZ, the machine is designed to lower power automatically to protect the IGBT. But SPG50K machines are recommended to work up to 80KHZ with full power.
4. Feature on low frequency:  primary coil voltage of SP machine is very high, when the frequency is low, this will cause  magnetic saturation of the magnetic core, so SP machine can not work well at low frequency; SPG50K machines do not have this problem.
5. Energy loss:  SP machines have much bigger high frequency transformer to cause much more energy loss than SPG50K machines.
6. Reliability:  Voltage of primary coil of SP machines can be 3000～7000V high,  so spark is easy to happen with SP machines.  SPG50K is more reliable without this problem. Secondly,  Soft switching technology is used in SPG50K voltage regulate circuit, this also improve the reliability very much.
7. Matching to the parts to be heated:  There are usually 4 matching taps in SPG50K machines, It is much easy to get the SPG50K machine to realize good matching whatever material is or application is.