Motor maintenance methods

Motor maintenance methods:

(1) observation method. Most of the breakpoints occur at the ends of the windings to see if they have collapsed or not.

(2) multimeter method. Using the resistance file, the "Y" -type connection will be a table bar in the "Y" -shaped center point, the other in turn connected to the first end of three-phase winding, infinite phase for the breakpoint; △ "type connection after the short-open connection, respectively, measured each winding, infinity, was the break point.

(3) test lamp method. Method with the former, such as the phase does not light for the open circuit.

(4) megger method. A phase whose resistance tends to infinity (ie, not zero) is a trip point.

(5) ammeter method. When the motor is running, the ammeter measures three-phase current, if the three-phase current imbalance, and no short-circuit phenomenon, the current phase of the smaller winding short-circuit fault.

(6) bridge method. When the motor one phase resistance than the other two-phase resistance, indicating that the phase winding part of the open circuit fault;

(7) current balance method. For the "Y" type connection, the three-phase winding can be connected in parallel, the introduction of low-voltage high-current AC, if the three-phase winding current difference of more than 10%, the current is small end of the open; Type connection, the first stator windings of a contact open, and then phase-phase access to low-voltage high-current, in which a small current phase is open circuit.

(8) broken cage scout check method. Check, if the rotor broken cage, the millivolt meter reading should be reduced.