Method for determining the end and end of a three-phase asynchronous motor winding
Method for judging the winding end and end of three-phase asynchronous motor by multimeter
One of the methods
Step 1: First, set the multimeter to R×100, measure the six lead wires of the motor junction box, and measure the two grounds separately to determine the three-phase winding. The specific method is: connect the red (or black) test pen to one of the lead wires; the black (or red) test pen sequentially contacts the other five lead wires; the two outlet ends of the path (refer to the larger deflection and the smaller resistance value) are one. Phase, and mark it (recommended with knotting or coloring as the identification mark) to distinguish it from the latter two phases, and so on to divide the six lead wires into three groups.
Step 2: Set the multimeter to set the current micro-ampere, such as the wiring diagram of the title map to determine the end of the two-phase winding. The specific method is:
(1) Set the multimeter to a current microamp;
(2) The red and black pens of the multimeter are connected to the two ends of one of the windings of the motor;
(3) Then, the two ends of the other phase of the motor are successively contacted with the negative electrode and the positive electrode of the dry battery (or the battery in the multimeter is used for testing) (9V or 1.5V battery);
(4) If the pointer of the multimeter is deflected in the forward direction, the terminal of the positive pole of the battery and the terminal of the negative end of the multimeter (black pen) are the same name; otherwise, the terminal of the negative pole of the battery and the terminal of the multimeter negative (black) are The same name end; as shown in the figure, the black dot is marked as the head end (or the end end), that is, the same name end. In the same way, the first and last ends of the other phase are determined.
Method 2: Star connection assay
Step 1: Determine the three-phase winding (the method is the same as above, pay attention to the simple and clear mark after each phase is detected; in order to distinguish the three-phase stator winding).
Step 2: Star connection determines the first and last ends of the three-phase winding
Specific methods: (1) set the multimeter to a micro-amp;
(2) short-circuiting each end of the three windings of the three-phase asynchronous motor to the red test lead, and connecting the other three ends together, and then receiving the black test lead;
(3) Rotate the motor at a constant speed to observe the deflection of the pointer.
(4) If the pointer is almost undeflected, the three selected line ends of each winding are the same name end (as shown in Figure 3). Otherwise, change the line.
Step 3 change line rules:
(1) Mark the three windings first and foremost, and predetermine the end number.
(2) The windings of one of the groups (assumed to be 5-6 ends) are always fixed as a reference.
(3) After the first and the last of the other two groups are separated, the specific methods (1)-(4) are discriminated. If there is still deflection, the other end of the group will be knocked off, and then according to the specific method (1) - (4), the correct end of the same name can be discerned.
