@deepak: If you do not have access to the specifications of the motor in question (such as a datasheet from the manufacturer), you would have to setup a test bench to determine no-load RPM, no-load current, stall torque, stall current, etc. Of course, this is not a trivial thing to make and requires experience in many fields, such as electronics, programming and mechanical engineering.
Iām considering a BLDC motor for my project but having a problem calculating the proper battery capacity to use. The reason is the the motor specs states (125 amps AC and 180 amps DC into the motor controller).
Is this motor consuming the 125 amps or the 180 amps?
can u please tell me the power rating and efficiency of a 24 volts motor and 10A currentā¦rpm is 115???
@zeeshan, There are various calculators available online that can help you calculate this. (Example)
@Sherif Thomas, It will do both, but the power source from the AC side is not the same as the DC side. The controller must use AC to work so we do not think it will work from of a battery pack.
mala tuzya lavdyachi size pathav.with pic
Sir. We are proposing to use a PMDC motor of 40 W capacity ( Nominal values - 24 V DC,2.3 A, 10 Ncm ,3600 RPM, Stall values - 67 Ncm, ), with a 100 : 1 gear box, to lift a load of 40 KG over a roller of 100 mm diameter.
Once the load if lifted up to the maximum height say 5 to 6M, it will remain there ever, (24 x 7 x 365 days) by applying a holding voltage of 4 V instead of 24 V.
What are the precautions , I should consider, and what will be the holding current . How the find the temperature increase. Please help
@Venkatesh Rather than constantly powering the motor, you might consider adding an electromechanical brake to the rear shaft - it would be far more efficient and consume a lot less current.
Sir we need to calculate Rpm of 5V DC motor. For this we are using 20 slot encoder disc. Can you please help us to correct the formula: rpm = 60*1000/((millis() - timeold)*rpmcount/20);
@Beena Thatās unfortunately beyond the scope of this article, but you can find a number of equations online. If you are using Arduino, there are many examples.
Hi, my question is how the stall torque and continuous torque that a motor can deliver is measured in the factory??? and another question is can you please introduce a user friendly software for me to simulate the magnetic and torque related parameters of a design???
Thanks.
I am wanting to use a small DC motor to drive a plastic fan blade inside a tube very close to the outer diameter of the fan blade. The motor specs show a nominal voltage of 7.2 VDC at 22,000 RPM under no load conditions drawing 1 amp. It is rated at ā6-12 VDCā with RPMs at 18K - 33K RPM. I want to operate the motor with two 3.72 VDC IMR 18650 Lithium batteries in series. The batteries are rated as 2.9 Ah high-drain batteries used for E-cigarettes. They are rechargeable. So the total voltage would be 7.44 VDC. I am concerned that if operated for more than a few seconds these batteries might overheat and, being Lithium, might explode. So, I need a current limiting resistor. I can calculate that E/I=R So 7.44/1= 7.44 ohms. But, with a load of the fan blade blowing air through a smaller tube will probably increase the current draw of the motor. The batteries are rated at 2.9 Amps for 1 hour (2900 mAh) and specify a discharge current of 35 amps. So, I plan to limit the current to ??? The motor specs do not show MAXIMUM current. I want to create a small battery powered device that replaces canned air for blowing out keybards and other small places that contain paper dust. So the output tube will go from a 1" fan to a 1/4" tube, I suppose. what do you suspect I will come up against? I feel I know just enough to get me into trouble. Thank you for any comments.
@MEDI The torque at many factories is rated based on the windings, coils etc. They then confirm with tests if the theory matches the actual build. Unfortunately we are not in a position to create such a tool at this time.
@John Clayton The post is far too long to answer in the comments section of a blog - can you please create a new topic on the RobotShop Forum? We would be happy to answer you there.
Coleman,
After reading most of these posts here, I must say that you have the patience of a saintā¦
i know what the nominal and stall current are, my question is suppose that i want to design a 3A motor(nominal current), how should i do that? is it just related to winding specs??? i mean that if i have a winding made of wire which is capable of holding 3A continuously, could i say that i have a 3A motor? and if yes, then how the stall current should be measured?
@Travis Appreciated. Itās not always the easiest to get started in robotics, so we do our best to help and provide information and answers.
@MEDI Thatās actually a level of support / knowledge beyond what we can provide here as it pertains to the specifics of DC motor construction (number of coils, coil diameter, material used etc.). Normally when you refer to a motor, itās in terms of maximum power (watts). Stall current can be measured (rather than theorized) simply by stalling the motor for a fraction of a second (but ideally not long enough to cause damage).
PMDC motorā¦5 Hp. how much maximum power can be achieved regularly?