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if you run the unloaded motor at max rpm the centrifugal forces will cause the motor to be totally destroyed
so it is advisable to not to run it at max rpm
it should be okay to run it till 50% of max rpm without loading it
Wiki User
∙ 13y ago
Wiki User
∙ 13y agoIn the case of a dc series motor, at the time of starting there'll be no back emf. So the full current will be applied and the motor will run in dangerous speed. This will damage the motor. So it is always started in loaded condition.
Wiki User
∙ 12y agoIn a DC series motor, load current=series field current=armature current and I directly proportional to flux then flux directly proportional to torque. So high starting torque makes high starting speed. If this motor starts without load the parts of the motor will affect.
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What motor must be never run without a load connected to them?
DC Series motor should never run without load connected to it because starting torque for DC series motor is infinite and running it on no load will damage the motor due to overspeeding.
How do you know if a three phase motor's winding is shorted?
You use a megger. This allows you to check what the condition of the insulation of the motor windings are. An ohms check on each phase should be an easy way if it reads OPEN then there's your bad phase. Otherwise there are diffrent types of 3 phase motors, could be the brushes, commutator, sliprings, many many things.
Is an ohmmeter connected in series or parallel?
You almost NEVER do. 1) The circuit should be off and/or disconnected when using an ohmmeter. 2) It should be in parallel with the component as far as the rest of the circuit is concerned, but alone in series with the device its measuring.
Can a 208 415 motor run on 230?
never heard of a 415 motor..
Can you run 1 HP single phase motor without neutral but with earthing?
Per code the earth should never be used as the sole source of ground. So no.
Why we apply load during starting a d.c.series motor?
a series motor started without load can go into a condition called runaway. The motor will rapidly accelerate to unsafe speeds literally pulling itself apart. This condition should never be allowed to happen. Consult a professional when installing any electrical equipment.
What motor must be never run without a load connected to them?
DC Series motor should never run without load connected to it because starting torque for DC series motor is infinite and running it on no load will damage the motor due to overspeeding.
Why dc series motor is always runs at loads?
At no load, the flux is only due to the residual flux, which is very small. the no load speed of dc series motor is very high. so the rotating part of the motor are damaged. hince dc series motor should never be run without motor.
When is the new h2o spin off series comin out?
The series is not going to come out because H20 was a terrible series that should have never been invented.
How long should a catalytic converter last?
A catalytic converter should NEVER go bad unless something causes it such as a RICH or a LEAN condition. What is a "RICH OR A LEAN CONDITION"?
What Is a 1928 G Series 2 Dollar Bill with a serial number E03011909A worth?
$5 to $10 depending on condition. Also, a bill's serial number almost never affects its worth. The date, series letter, and condition are the major factors determining value.
How do you know if a three phase motor's winding is shorted?
You use a megger. This allows you to check what the condition of the insulation of the motor windings are. An ohms check on each phase should be an easy way if it reads OPEN then there's your bad phase. Otherwise there are diffrent types of 3 phase motors, could be the brushes, commutator, sliprings, many many things.
Why a DC series motor should never be stared without load?
since torque is proportional to flux and armature current . Flux for dc shunt is constant . torque is proportional to armature current only. And initially armature current is very low hence it cannot be started at load .
How fast should a tractor trailer vehicle be driven when backing?
As slow as possible. You should never be on the high end of the reverse gear, and the motor should be at idle as you're backing.
Is an ohmmeter connected in series or parallel?
You almost NEVER do. 1) The circuit should be off and/or disconnected when using an ohmmeter. 2) It should be in parallel with the component as far as the rest of the circuit is concerned, but alone in series with the device its measuring.
How much it worth a 10 dollars bill of a series D57554699C year1950?
$12 to $15. The serial number almost never affects a bill's value. Date, condition, and series letter (near the date) are the most important factors.
Why dc series motor is never started on light load?
the speed N is inversely proportional to armature current I. At light loads this current is very small. Hence motor will run at very high speed when started on no load/light load.........
