Interested to Buy Any Domain ? << Click Here >> for more details...
Why material of brush is carbon in motors why not other
material.
- 5 Answers
- 9470 Views
- NTPC, I also Faced
- E-Mail Answers
Answer Posted / keepup
as per my limited knowledge i think the reaso y brush is
made of carbon is coz carbon has a negative temperature
coeficient of resistance, that is due to friction between
the brush and rotor, temperature is developed. as a result
the resistance of carbon brushes will decrease. for
instance if copper or aluminum brush is use, then when temp
increases at the contact pt between the brush and rotor,
resistance of the copper or aluminum brush will increase
resulting in loss of energy usually in the form of heat and
may lead to burning of the brushes.
| Is This Answer Correct ? | 6 Yes | 0 No |
Post New Answer View All Answers
When a single pase capacitor run motor- run on 230vac and Case(1)run with 8 Mfd 250 vac.capacitor , Case( 2) run with 8 Mfd 400vac capacitor. What is difference between both case regarding power ,efficiency etc?
can i able to get bhel previous exam question paper?
what is Insulation monitoring device. where it is used? (in switchgear room or control panel or in field equipment)
what are the major & minor faults that occur in an inverter and in UPS ? And how to repair and resolve them ?
TYPE'S OF BREKAR ,WHAT IS TRANSFORMAR & SAFTY. STARTER DOL & STAR DELTA STARTER.
when the time of backcharging the transformer three phases only enough or three phase with neutral is must.from these which one is the best one.
diff b/w normal grounding and resistance grounding
what happen if drive input fail momentry at 48.5 HZ frequency?
How will you define capacitance?
Two bulbs of 100w and 40w respectively connected in series across a 230v supply which bulb will glow bright and why?
What is safety of Ht panel
If mutual flux is 1.2wb & power factor is 0.8 lag , then what is the Useful flux of a transformer?
Distribution transformer we provided 2 separate earthing pit for Body and 2 separate earthing pit for neutral,we can not connect separate body earthing pit to other earthing pit but we do metal glanding in secondary side cable termination in both side, transformer and PCC panel (LT Panel), is this safe for transformer and other equipment?
What is the safety of UPS?
In single phase capacitor motor, if the motor rotate reverse direction then how much power will be consumed by the motor and why?
