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Why are the brushes of a dc machine always placed at the neutral points?
Wiki User
∙ 13y ago
The function of brush is to collect current from rotating commutator and supplies the current to external stationary load.
The brushes of a DC machine are placed at neutral points because the current in the rotating part drops to zero at the neutral point.
If brushes are placed in location other than the neutral points, then the current may be switched off and it causes magnetic field and it may also create voltage spikes and arc at brushes.
Muhammad Abdullah Ba...
Wiki User
∙ 13y agoThe brushes of a DC machine are placed at the neutral point because this is the point when the current in the rotating part drops to zero. If the brushes are not located at the neutral point, the current is suddenly switched off and the magnetic field collapses causing high voltage spikes and arcing at the brushes - this quickly destroys the brushes. If you look inside small hobby dc motors you can often see this arcing.
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Why is brushes placed at MNA in a dc generator?
to avoid sparking ,since their is no e.m.f induced in magnetic neutral axis.
What is exactly the function of Neutral link in an electrical circuit?
To protect a circuit, we use a fuse or circuit breaker. The fuse or circuit breaker must always be placed in the lineconductor, never in the neutral conductor. So, if we want to completely isolate a circuit from the supply, we must remove the fuse from the line conductor, and open the link in the neutral conductor. A 'link' is a non-fusible metal break point in the neutral.
What is meant by neutral grounding reactor?
Neutral-earthing reactors or Neutral grounding reactors are connected between the neutral of a power system and earth to limit the line-to-earth current to a desired value under system earth fault conditions.
Why Do not clamp live plus neutral cable in Clamp meter?
A clamp-on meter works by measuring the magnetic field set up around a conductor. Because the currents in the line and neutral conductors flow in opposite directions, their fields cancel and the clamp-on meter has nothing to monitor. So it must be placed around either the line OR the neutral conductor -not both!
You can use neutral to autotransformer?
Yes, but the transformer must have both the hot and neutral to work as designed. A auto-transformer is not a variable resistor that could reduce current/voltage by a change in the resistance which could be used in the hot and or neutral wire. An auto-transformer is designed to have the hot wire and neutral on each end of the winding with a variable tap in between. The resistance of the transformer and the inductance will effect the circuit to a limited way if placed in the neutral but this effect will not vary the voltage over the full range, the amount of voltage reduction will vary with the load's current draw, see ohms law. Neither a resistor or a auto-transformer connected in the neutral line only will increase the voltage above the level of the input like a correctly connected auto-transformer . Stanley
Why is brushes placed at MNA in a dc generator?
to avoid sparking ,since their is no e.m.f induced in magnetic neutral axis.
Why are brushes staggered in dc motor?
To avoid sparking they need to be placed at zero point
Why brushes are placed at neutral axis in dc machine?
this is the only way the motor will turn in a 2 pole motor if you move the brushes 90 degrees one way the poles will attract each other 90 degrees the other way they repel and there would be some oscillation until it did the shift to the non repelling state the brushes arent at the geometric null since when its running the null shifts a bit because of residual magnetism the brush rings can be shifted a bit to get the dynamic null at normal load conditions, less arcing, less brush wear
What do hair salons use to clean brushes?
Salons use a product called "Ship-Shape" Comb and Brush Cleaner. There is also a small machine with plastic bristles that rotates rapidly to remove hairs that are caught in brushes. After using Ship Shape, the combs, brushes, clips, etc., are placed in a disinfectant called Quaternary ammonium compounds or "Quats" and soak for a minimum of 10 minutes. Then the tools are rinsed with clean water and allowed to dry.
Which is the safest position for the switch when an appliance is used?
Your question is rather vague but, for a.c. systems, a switch must always be placed in the line conductor, neverthe neutral conductor.
In a dc generator brushes are placed in which side to avoid armature reaction?
along the M.N.A axis along the M.N.A axis
What happens when charged objects placed near the neutral objects?
There will be an attractive interaction between the charged object and the neutral object.
What happens when a neutron is added to a neutral atom?
well, since a neutron = 0 charge placed into a neutral which is has no charge, it stays the same.
What is the name of the machine that checks your heart rate and your pulse?
I think your talking about the machine they use outside your body, placed on your chest and it shows a picture of your heart on a screen? This would be called an Ultrasonagraphy machine. The test is nearly always done by a certified ultrasonagrapher who knows how to read what is showing on the screen.
What is exactly the function of Neutral link in an electrical circuit?
To protect a circuit, we use a fuse or circuit breaker. The fuse or circuit breaker must always be placed in the lineconductor, never in the neutral conductor. So, if we want to completely isolate a circuit from the supply, we must remove the fuse from the line conductor, and open the link in the neutral conductor. A 'link' is a non-fusible metal break point in the neutral.
Why is a girl is always placed in the kitchen?
because if a boy will be placed there will be a disaster!
Why switch is always connected in the phase wire?
First of all, the correct term is 'line' and not'phase' wire. The reason a switch is always placed in the line conductor, rather than in the neutral conductor, is that its function is not simply to break the circuit, but also to ensure that the circuit's load is disconnected from the line potential. If the switch were to be placed in the neutral conductor, it would still break the circuit, but the load will still be at line potential and present a shock hazard to anyone attempting to work on the load (e.g. to remove a lamp from its holder).
