Blower discussion
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I currently have a blower of the C30-1.4 model; it has an air intake volume of 30 m3/min, and the pressure at the blower’s outlet is 40 kPa. I use variable frequency starting for this blower, but the manufacturer said that the motor I have is not suitable for variable frequency starting. Is this statement correct? Is it necessary to use a motor designed for variable frequency operation when using variable frequency starting? And how to adjust the inlet and outlet valves of the fan as well as the frequency of the inverter so that the motor operates at maximum airflow? My fan is being used in experiments, and the air volume needs to be adjusted from low to high. How can I make the fan meet this requirement? For example, the air volume should range from 10 m3/min to 30 m3/min, or even higher
If you use a regular motor, it can be used for variable-frequency starting, but it cannot operate for long periods at low frequencies; the operating frequency must not exceed 50 Hz. If you use variable frequency drive during testing, there is no need to adjust the control valve; just open the valve to its maximum position and use the variable frequency drive to adjust the flow rate you need. If your motor does not have a variable frequency drive, you can add a fan behind the motor to cool it down.
You can adjust the inlet vanes of the fan to control the airflow volume you desire, thereby meeting your requirements.
Generally, it is quite difficult to increase the maximum airflow of fans, unless the air volume is reduced by adding air doors to the system, as mentioned above. If the required air volume is not achieved even with the dampers fully open, 1. Check the performance curve of this type of fan to determine whether its air volume range meets your requirements. 2. Change the fan speed. (The change in air volume is linearly related to the rotational speed and cubically related to the power).
Ordinary fans can be started using variable frequency, but to ensure they operate properly after starting, and if variable frequency operation is required throughout their operation, then the selection of the motor becomes important
Excuse me, sir/sister on the 4th floor: what are inlet guide vanes?
The inlet guide vanes he mentioned should be the inlet control dampers.
Regarding the motor to be used, several factors need to be considered. If the motor does not need to start frequently, and the frequency adjustment range is not very wide, a regular motor can be used as a substitute. On the other hand, an inverter-driven motor is required, as regular motors have limited resistance to harmonics and voltage surges, which can easily lead to their damage.
The comments on floor 9 were very professional; thank you