On 2018-08-08 14:48:54
Several precautions for debugging explosion-proof fans
1、 On the start of explosion-proof fan.
When the explosion-proof fan is started, it can be started with full pressure or reduced pressure. However, special attention should be paid to which starting mode to choose. When full voltage starting is adopted, the voltage must be five to seven times of rated current to start normally. The square of voltage must be proportional to the torque scale when starting with step-down.
There must be two kinds of depressurization. One is to use step-down starting when the capacity of the power grid is insufficient; the other is to adopt step-down starting when the power is more than 11 kw.
2、 About the test run.
During the test run of explosion-proof fan, it must be ensured that not one person is operating, and at least two people will complete the test run. One person is used to control the power supply, and one person is used to monitor the operation of the explosion-proof fan in real time. If abnormal conditions are found, the first thing to do is to stop the explosion-proof fan immediately, and then carry out the next debugging stage.
First, the steering of the impeller. The thing to do is to observe how the explosion-proof fan impeller rotates and whether the direction is correct;
Secondly, the current situation. In the case of normal operation of explosion-proof fan test run, observe the current, check whether the operating current is stable and balanced, and whether the current is much larger than the rated current.
Whether it is current or steering, if there are abnormal conditions, it is necessary to stop the operation of the explosion-proof fan being tested and conduct necessary inspection.
Finally, let the explosion-proof fan run normally and observe the situation. After it runs for five minutes, stop the explosion-proof fan to see if it has any abnormal conditions. If there is no abnormal situation, the explosion-proof fan can run normally and carry out the next work.
3、 Precautions for test run of explosion-proof fan.
During the test run of explosion-proof fan, there is also a notice, especially for the test run of two speed fan, it is necessary to start the fan at a low speed first, judge the rotation direction of the impeller, and see if there is a problem in the rotation direction; for the start-up at a high speed, it is necessary to wait until the explosion-proof fan stops. If it is urgent to start, it is easy to cause the rotation direction of the impeller when rotating at high speed, which will trip the switch of the explosion-proof fan, and cause unnecessary damage to the motor in serious cases.
4、 The problem of input power of explosion-proof fan.
Under the condition that the explosion-proof fan can operate normally, the thing to be done is to check the input power supply of the explosion-proof fan to see if they are all normal. In the same way, the input power supply of explosion-proof fan shall be within the control range of rated current, and shall not be higher than the rated current. Of course, if the input current of the explosion-proof fan exceeds the rated current and still continues to operate normally, in this case, it is necessary to check the voltage of the explosion-proof motor to see if the voltage of the explosion-proof motor is normal.
5、 About the fan box.
As for the power of the motor, it needs to be specially explained. It is not the power of the motor of the explosion-proof fan when the air outlet is fully opened, but the mechanical loss and due reserve of the motor of the explosion-proof fan under certain working conditions. For example, the air outlet of the explosion-proof fan does not increase other external resistance, or the air outlet is not connected with the pipe, then the explosion-proof fan is actually running without load, which is easy to cause the motor of the explosion-proof fan to be burned. For the sake of safety, it is necessary for the staff to add a valve at the inlet pipe or air outlet of the explosion-proof fan, close the valve when the fan is started, and slowly open the valve when the explosion-proof fan is in normal operation until the working condition is reached. Of course, during this period, it is necessary to observe whether the current of the explosion-proof fan exceeds Specified value. If the specified value is exceeded, the staff is required to make a solution in time for future trouble.