The air compressor start mode is mainly divided into: direct start, star-delta start, soft start mode, frequency conversion start, air compressor energy-saving drive all-in-one machine, what is the difference between these five start methods, today I will come to you introduce.
1. Direct start mode
Mainly used in low-power air compressors, the starting current is generally 7-8 times the rated current, and the moment of starting is more harmful to the grid, usually composed of contactors, air switches, and thermal relays.
2. Star triangle start
The starting current is 3-4 times the rated current, and the starting current is smaller than the direct starting current; there will be a peak current of about 4-6 times the rated current during the star-angle switching process; at present, due to cost reasons, this method is widely used in the air Press start and stop
3. Soft start mode
The soft starter is used to control the main motor of the unit, and the control circuit is triggered by the gate of the thyristor to control or limit the starting current of the motor
The starting current is 2-3 times of the rated current, and the starting is relatively stable
Need to add a bypass contactor, switch to bypass work after startup
The soft-start mode cannot adjust the speed, and cannot do anything about the corresponding compressor speed adjustment and energy-saving mode
The soft start integrates a variety of protection functions, making the second circuit simpler and easier to maintain
Integrated communication port, easy to connect to the overall system
4. Frequency conversion start mode
The starting current is small, the required grid capacity is the smallest, and the starting is the most stable
The compressor speed can be adjusted, the speed of the compressor can be adjusted according to the actual load, and energy saving can be realized
Compared with the soft starter, the protection is more abundant, the diagnosis is easier, and the interpersonal interface is simple and easy to operate
5. Drive all-in-one machine
The starting current is small (2-3 times), and the impact on the motor and the machine head is very small
Using microcomputer intelligent control technology, the system automatically collects the temperature, ambient temperature and customer air consumption of the on-site air compressor in multiple channels, and scientifically controls the start according to the air compressor's loading and unloading operation curve.
Stop time, under the condition of protecting the motor, machine head and ensuring the user's safe air consumption, realize the maximum unloading and shutdown of the air compressor and save energy
The start mode cannot be tuned frequency or constant voltage