Check the pressure on the brush and the contact with the collector ring
(1) The hook pull brush can be used to press a thin and smooth piece of paper on the brush with a brush (two brushes and symmetrical) or a line that passes through a horizontal hole at the upper end. Between the collector rings. Use a small spring balance to pull the upper end of the brush and pull the spring balance along the radial direction of the collector ring (in the direction perpendicular to the working face of the collector ring) while gently pulling the paper out. When the paper sheet can be taken out, it is the moment when the brush just leaves the surface of the slip ring, and the value of the spring scale is the pressure of the brush.
(2) Method for judging whether the brush pressure is normal
The pressure exerted by the brush on the surface of the slip ring is determined. The measured brush pressure is divided by the actual contact area of the brush and the collector ring to obtain the pressure applied to the collector ring by the brush.
(3) Check the contact area between the brush and the slip ring
The inspection of the contact area between the brush and the slip ring can be roughly obtained by visual inspection. If a more accurate value is required, a layer of red or blue (blue) ink or white chalk is applied to the brush working surface in advance. Wait, put the brush into the brush box, adjust the pressure, turn the rotor of the motor for several turns, remove the brush, and view the area of the erased coating. The area of the area of the brush working area is The percentage of the contact area.
● Conducting a stall test at low voltage
The stall test at low voltage is an item of inspection test, and its purpose is the same as that of a conventional cage rotor motor. The applied voltage and the data to be measured are the same as those of the conventional cage rotor motor inspection test. During the test, the rotor should be blocked. If there is no brushing device, the rotor winding should be short-circuited on the collector ring or the three-phase lead-out wire should be connected and short-circuited. If there is a brush-lifting device, the brush-lifting device should be placed in the operation. "position.