A soft starter is a motor control equipment that integrates soft start, soft stop, light load energy-saving, and multifunctional protection. Realize smooth and impactless starting of the motor throughout the entire starting process, and adjust various parameters during the starting process according to the characteristics of the motor load, such as current limit value, starting time, etc.

Selection guide:

There are currently three popular types of soft starters in the market: online type, bypass type, and built-in bypass type. Online soft starters are basically foreign brands, with a market share of about 1/4, mostly focused on image and ignorant engineering. Over half of them use bypass type soft starters. Since the introduction of built-in bypass type in 2003, the popularity of built-in bypass type soft starters has begun. Through the above introduction of the technical progressiveness of built-in bypass soft starter, the reader has a rational understanding. The author uses data comparison to achieve quantitative analysis, as shown in the attached table. The cost in the appendix refers to the manufacturer's public quotation, and the user's purchase price is generally lower than this price.

The bypass type soft starter is superior to the online type soft starter, while the built-in bypass type soft starter is superior to the bypass type and online type soft starters. But the more advanced the price, the lower the cost, which is a general rule of high technology. Compared by brand, online soft starters are 1.5 times more expensive than bypass soft starters, while bypass soft starters are 1.4 times more expensive than built-in bypass soft starters (excluding the price of contactors). In terms of energy consumption, the online type soft starter is about 10 times that of the bypass type soft starter, while the bypass type soft starter is about 7 times that of the built-in bypass type soft starter.

There are over 300 million kW electric motors in operation nationwide, and it is estimated that 40% of them require soft starters. About 120 million kW electric motors use soft starters. In terms of investment, using an online soft starter requires over 25.2 billion yuan, using a bypass type soft starter requires over 16 billion yuan, and using a built-in bypass type soft starter requires over 10 billion yuan. In terms of total energy consumption, all online soft starters are used, with an annual power consumption of 6.3 billion kWh, which is equivalent to the annual power generation of an 800000 kW power plant. The total annual power consumption of all bypass type soft starters is 630 million kWh, which is equivalent to the annual power generation of an 80000 kW generator. All adopt built-in bypass type soft starters, with an annual total power consumption of 80 million kWh. Equivalent to an 8000kw generator generating one year of electricity. Using all bypass type soft starters can save 5.6 billion kWh of electricity per year compared to using all online type soft starters. If all built-in bypass type soft starters are used, it can save 550 million kWh of electricity per year compared to all bypass type soft starters.