Diyvehiclerepair
If a rotor bar is broken, the amplitude of the beat increases with load. In addition, a cracked rotor will lead to a localized increase in temperature, which in turn causes bowing and uneven expansion. This results in imbalance, additional vibration, and side bands that are related to slip frequency.
- How do you check a motor rotor?
- What causes rotor bar failure?
- What is broken rotor bar fault?
- What does a bad rotor sound like?
- Can you drive with bad rotors?
- What is a motor rotor bar?
- What is slip of induction motor when rotor is blocked?
- What is not effect of single phasing on 3 phase induction?
- What is rotor bar pass frequency?
- How many rotor bars does my motor have?
- How is rotor bar frequency calculated?
- What will a warped rotor do?
- How do you know if your front or rear rotors are bad?
- What do rusty rotors sound like?
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.
What causes rotor bar failure?
MAGNETIC STRESS
Dynamic forces are generated due to slot leakage flux, which are proportional to the rotor current squared. These magnetic forces vibrate the bar and displace it radially. This magnetic force will cause the rotor bar to bend and could result in fatigue failure.
What is broken rotor bar fault?
Broken rotor bar is one of the commonly encountered induction motor faults that may cause serious motor damage to the motor if not detected timely. ... Specifically, the Hilbert transform first extracts the envelope of the motor current signal, which contains broken rotor fault-related frequency information.
What does a bad rotor sound like?
Noises When the Vehicle Brakes
Warped rotors can cause a squeaking noise when the brakes are applied. They can also make a scraping or grinding sound when they're warped and worn down. The squealing noise, however, can also be made by brake pads that are worn out.
Can you drive with bad rotors?
If you suspect you have warped rotors or your brakes are failing, it is important that you avoid driving your vehicle and contact a mechanic right away. Driving with warped rotors potentially will result in a brake system failure, which can cause injury to yourself and those around you.
What is a motor rotor bar?
The rotor windings are made up of rotor bars passed through the rotor, from one end to the other, around the surface of the rotor. The bars protrude beyond the rotor and are connected together by a shorting ring at each end. The bars are usually made of aluminium or copper, but sometimes made of brass.
What is slip of induction motor when rotor is blocked?
Process of Testing of Blocked Rotor Test of Induction Motor
In block rotor test, the low voltage is applied so that the rotor does not rotate and its speed becomes zero and full load current passes through the stator winding. The slip is unity related to zero speed of rotor hence the load resistance becomes zero.
What is not effect of single phasing on 3 phase induction?
If single-phasing occurs when the motor is not working, the motor will fail to start. It will merely give a humming sound. Current drawn by it under this condition will be 87% of the starting current under the normal condition.
What is rotor bar pass frequency?
As a loose rotor bar passes a winding slot, the magnetic force causes it to momentarily lift and then drop. The frequency, then, is the number of windings slots x RPM (Winding Slot Pass Frequency or WSPF). The number of winding slots will be between about 25 and 100.
How many rotor bars does my motor have?
One other method to determine the number of rotor bars it to examine the the RBPF +/- K*2LF pattern in vibration: take vibration using high Fmax (above RBPF) and high # lines (to get good frequency resolution) - something like Fmax=300,000, lines =6400. Look for the set of peaks separated by by 2*LF.
How is rotor bar frequency calculated?
Loose or open rotor bars in AC induction motors are indicated by a 2 X line frequency (2 FL) sidebands surrounding rotor bar pass frequency and/or its harmonics (rotor bar pass frequency = number of bars X rpm).
What will a warped rotor do?
Because of this mass amount of heat, the surface of the brake rotors can become uneven over time, which is often referred to as warping. This can cause your vehicle's brakes to become jittery and less effective. Brake rotor warping isn't as severe as it sounds.
How do you know if your front or rear rotors are bad?
Warped rear rotors will make the car shake when braking. Warped front rotors will make the steering wheel shake when braking. The front wheel will wiggle in your hand if a front rotor is warped. A warped rear rotor will make the car shimmy or shake under moderate to hard breaking.
What do rusty rotors sound like?
A buildup of rust on your brake rotors can cause your brakes to make a squealing or squeaking noise. If your vehicle sits outside overnight, moisture from rain, snow or dew can collect on the surface of the brake rotors. This moisture causes a layer of rust to develop on the rotor.
