Ease of manufacture and maintenance, high reliability contributed to the widespread use of induction motors in various industries. With a power of more than 0.5 kW, they are usually performed three-phase, with a lower power - single-phase. Based on this, it can be assumed that the need to connect a three-phase motor to a single-phase network occurs very often.
Necessary
- - single-phase electrical network of alternating voltage 220 V;
- - working and starting capacitors.
Instructions
Step 1
Calculate the running capacitor for connecting the motor to a single-phase network. The capacitance of the capacitor depends on the power of the motor. To calculate the capacitance of a capacitor (in μF), multiply the rated motor power (in kW) by 66. For example, a 1 kW motor would require a 66 μF capacitor. To obtain a capacitor of this capacity, several parallel-connected capacitors with a lower capacity can be used.
Step 2
If the capacity of your motor exceeds 1.5 kW, when connected, it will either not rotate at all, or it will pick up speed very slowly. To start such a motor, you need to use a starting capacitor. Typically, the starting capacitor has 3 times the capacity of the working capacitor.
Step 3
Connect the motor in a star or delta connection to a single-phase network.
Step 4
When connecting the motor according to the "delta" scheme, connect one of the windings to the ~ 220 V. In parallel, turn on the working capacitor. In parallel with the working one, connect a starting capacitor with a button. Connect the beginning of the second winding to the end of the first, the end of the second winding to the beginning of the third, and the end of the third winding to the beginning of the first.
Step 5
To connect the motor according to the "star" scheme, two phase windings must be connected directly to the network, and the third phase winding through a working capacitor - to one of the first two.
