The most common test methods for disassembled offline rotor testing utilize magnetic viewing film. Many facilities use a growler apparatus to induce a current in rotor bars under evalu- ation and use magnetic field viewing film to detect the presence of a magnetic field for each rotor bar as seen in Fig.
How do you check a motor rotor?
HIGH CURRENT ROTOR TEST – This test is performed by applying high current through the shaft of the rotor (rotor out of stator) and thermally scanning (infrared or thermoscan) the rotor O.D. searching for shorted laminations. These shorted laminations cause localized hot spots which cause uneven heating of the rotor.
How do you know if your car rotors are bad?
One of the first symptoms commonly associated with bad brake rotors is noise. If the rotors are warped (meaning not perfectly flat) or severely worn, they may produce squealing or squeaking sounds. Usually, warped rotors will produce a squeak, while severely worn rotors will produce a scraping sound.
How do I know if my induction motor is bad?
With a multimeter set to low ohms (usually 200), test between each winding terminal and the metal casing of the motor. If there is any reading on any of these then the motor is bad, do not use it. You may find that when it runs ungrounded that the casing becomes live at up to supply voltage.
Can a commutator be repaired?
Mold-type commutators are not repairable and must be replaced if damaged. When a commutator comes in for a repair, units are disassembled and rebuilt with new copper and mica segments using the same quality assurance processes applied to new commutators.
Do you have to replace all 4 rotors at once?
Although it is recommended by Ford to replace all four wheel brakes at the same time for safety, your idea should be OK. If you decide to get them replaced, consider enlisting a certified mobile mechanic who can service your brake pads and rotors at your own convenience.
How long can you drive with a bad rotor?
Vehicle brake rotors can last for between 30000 and 60000 miles depending on your driving styles and vehicle type. In some cases, the brake rotors could hold out for a little bit longer.
What happens if you put new pads on bad rotors?
If new brake pads are put onto a vehicle with damaged rotors, the pad won’t properly contact the rotor surface, reducing the vehicle’s stopping ability. Deep grooves that have developed in a worn rotor will act as a hole-puncher or shredder and damage the pad material as it is pressed against the rotor.