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Because full speed is unloaded. As you load the motor, speed decreases, and slip increases, with an accompanying increase in current.
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What is the Difference maximum unit current draw and nominal unit current draw?
Maximum current is defined by the rated KW of the device, say Motor. The motor may not run at its maximum rated capacity all the time. Nominal current is drawn when motor runs at nominal load.
What is locked rotor?
Locked rotor current is the amount of current a motor would draw if you energize the motor and the rotor (the spinning shaft) doesn't spin.
What is locked rotor current?
"Locked Rotor Current" also called LRA which stands for Locked Rotor Amps, is commonly found on electric motor nameplates. Locked Rotor essentially means the motor is not turning. The current or amps in this case have to do with the amount of electrical energy required to start the motor. At the instant the motor is switched on, it is not turning, and draws the maximum current. As the motor starts to turn, the current goes down. This required energy is much greater than the Full Load Amps or Running Amps, which is the current drawn when the motor is running at normal speed under full load. The current required to start the motor will depend on the type of motor as well as the specified design voltage required for the motor, typically the higher the voltage, the lower the required amperage or current. The term also applies to equipment such as Air Conditioners which have an enclosed motor inside the compressor, as well as the condenser fan(s) etc. Depending on the type of motor, LR current can be anywhere from 3 to 8 times the normal running current, also called RLA, or running load amps.
Is it common for electric bathroom vent motors to trip an GFCI receptacle?
Unfortunately GFIs don't like motor loads. The start up current required to start the motor is often 125-150% of the running load current draw. This initial spike in current draw when the motor is energized is sometimes "misread" by the GFI as current going to ground or an imbalance between the hot and neutral current. If your GFI has tripped numerous times, it is likely getting "weak". Try replacing it first. If it still continues to trip, replace your vent fan motor.
What is the Significance of back emf in dc motor?
Fig. (4.3)ZN/60 A) is large and hence the motor will draw less armature current and vice-versa.4.4 Significance of Back E.M.F.The presence of back e.m.f. makes the d.c. motor a self-regulating machine i.e.,it makes the motor to draw as much armature current as is just sufficient todevelop the torque required by the load.Armature current,abaREVI−=(i) When the motor is running on no load, small torque is required toovercome the friction and windage losses. Therefore, the armaturecurrent Iais small and the back e.m.f. is nearly equal to the appliedvoltage.(ii) If the motor is suddenly loaded, the first effect is to cause the armature toslow down. Therefore, the speed at which the armature conductors movethrough the field is reduced and hence the back e.m.f. Ebfalls. Thedecreased back e.m.f. allows a larger current to flow through thearmature and larger current means increased driving torque. Thus, thedriving torque increases as the motor slows down. The motor will stopslowing down when the armature current is just sufficient to produce theincreased torque required by the load.(iii) If the load on the motor is decreased, the driving torque is momentarilyin excess of the requirement so that armature is accelerated. As thearmature speed increases, the back e.m.f. Ebalso increases and causesthe armature current Iato decrease. The motor will stop acceleratingwhen the armature current is just sufficient to produce the reduced torquerequired by the load.It follows, therefore, that back e.m.f. in a d.c. motor regulates the flow of armature current i.e., it automatically changes the armature current to meet theload requirement
What would be the horse power required in a 3-phase motor to replace a .5 horsepower single phase motor.?
You still need the same horsepower. The advantage of the three-phase motor is that it will draw lower current.
If defective blower motor draws more current than a good motor because?
defective motor will not run, also cause the blower motor speed resistor to burn out and eventually blow the fuse. a motor with defective bearings will draw excessive current causing either the fuse to blow or cause the motor to overheat
What is the Difference maximum unit current draw and nominal unit current draw?
Maximum current is defined by the rated KW of the device, say Motor. The motor may not run at its maximum rated capacity all the time. Nominal current is drawn when motor runs at nominal load.
Why would the blower motor on your 2000 Cherokee operate intermittantly and sometimes not at all no matter what the speed is set at?
A loose connection at the motor and/or bad ground at the blower motor. If it is getting current then the motor may have a bad spot/ high amp draw and need to be replaced.
When does a motor draw current more than its rated current?
This is a good indication that the motor is being overloaded. If the motor load is belt driven, remove the belt and then check the motor amps. If it goes back to normal FLA then there is a problem with the driven load. If the motor amperage stays high check the motor bearings for the problem.
What is locked rotor?
Locked rotor current is the amount of current a motor would draw if you energize the motor and the rotor (the spinning shaft) doesn't spin.
Is a load and a motor the same thing?
when machine is taking electrical supply and produces flux, torque etc inside and gives mechanical (rotational) output it is MOTORbut when this motor is connected to some thing which results in drawing current and work to be done, that thing is LOADwithout any load motor has maximum speed and by increasing load speed decreases..AnswerAnything connected to a supply which draws current is a 'load'. 'Heavy loads' draw a lot of current, whereas 'light loads' draw little current. So a motor represents a load to the electrical supply; this applies whether the motor is driving a 'mechanical load' or not. We use the term 'mechanical load' to describe whatever (fan, compressor, pump, etc.) is being driven by a motor.
In a fan fast turn or slow turn takes more current?
Fast speed requires more current than slow speed on the same motor unless the slower speed is caused by additional load. Two motors, one turns 1725 RPM and the other equal hp motor turns 3450 RPM, each draw same current because AC motors run at speeds close to the synchronus speed of the rotor poles. 2pole, 3600; 4pole, 1800.
Why would a dc motor show high amps no voltage and struggle to turn?
The current flowing in a dc motor is determined by (Applied voltage-Motor EMF) divided by armature resistance. The motor emf is a function of the field excitation of the motor and the speed at which the motor turns. When the motor starts, there can be no EMF because motor speed is 0 rpm. Therefore the motor will draw more current. But as the motor begins to speed up, if it has field excitation, it has to build up EMF and the current will drop. So : If the motor shows high amps and no voltage and struggles to turn the possible reasons are: 1. The motor has no excitation - The permanent magnets are weak or the field winding is faulty or the field is not being supplied. 2. The armature winding is faulty - it has shorted windings. This assumes your supply is healthy of course.
What happens if dc is given to induction motor?
It will draw a heavy current and coils will be brunt.
What current will a 100w electric fan motor draw when you plug it into a 240v wall socket?
0.4166666
Why does a slow motor create high amps?
Excessive resistance (drag), will cause motor to draw more amps (current flow) to operate.
