Search results for query: *

Can anyone recommend me a way to calculate Mean Time Between Repair (MTBF) of BLDC motor. Is there a way of estimating it without the help of the manufacturer? The engine specs are: 2 poles 21 winding inrunner 1:4.4 transmission 76.1 mm length 27.6 mm diameter 15 Ampere 15 volt max rpm 60k...

There are people in this forum who helped me with motors before so I don't see anything wrong with it.

Can I rely on saying that the starting torque of a BLDC engine is the multiple I_max*Kt . I find it problematic because I am not sure BLDC controllers are entirely predictable I would be glad for some help..

thanks clyde38 this helps with the theory But the bottom line as you said is that I can't be sure of the stall torque because it depends on current that the controller of the bldc motor allows me draw and on the manufacturer.

I've noticed somebody calculating the starting torque by the equation T_stall= K_torque*(V_nominal/R_armature) Does that mean the motor has to overcome the large amount of current it has at the beginnig can anyone elaborate? thanks

Is there anyway of predicting what will be the starting torque of a BLDC motor (BRUSHLESS DC MOTOR) without asking the manufacturer? Can I know the starting torque by consulting the manufacturer of the BLDC motor controller?

Clyde 38 I have another question for you. The stall torque in the spreadsheet you gave me is calculated by finding the current running at nominal voltage when no emf is induced. From what I understand you refer to the current as the starting load. Can you explain why? what about the friction...

thanks Clyde38 this excel sheet is really useful.I havn't understood all of the equations but I am on the way. The excel sheet that motorman sent is a bit above my current level of understanding but thanks anyways

Here is the catalog: http://files.engineering.com/getfile.aspx?folder=6862f175-95ee-4fbd-bc02-ad8308e5fa8e&file=Hacker-2008-WEB_28+29-1.pdf

Motorexpert, I am looking at a R/C motor company called Hacker motors Catalog. They don't have a lot of specs in their brochures. Regrading the maximum power the differences. Although I would achieve similar power outputs I would notice the differences in power inputs. Since there's a...

Looking on a BLDC motor catalog for motors with the same iron there are different motor windings but similar maximum power ratings. Other than that I know the operating current, no load current, armature resistance, terminal voltage 1. Just to be sure since it has a permanent magnet the no load...

thanks Clyde38. I've downloaded the book and still havn't looked at it.

I have catalog specs for a brushless DC motor saying [I_0] no load current @ 8.4V = 3.84[amp] [R_a] = 0.0063 Continuous Current = 45 Amp No. Winding = 6 Voltage= 14.8 - 18.5 max power = 700Watt (15 Sec) Kv=5000RPM/Volt 1. Is it possible to find the motor torque constant with the help of...

On the matter of added current conduction.... Looking on a BLDC motor catalog for motors with the same iron I've noticed different motor windings but similar power ratings. Since you have a thicker wire more current will be drawn from the power supply. Although the current goes up the voltage...

thanks a lot Curt....

thanks for the answer Curt. and another one The numerical equality between Ke and Kt is based on making no references to mechanical or electrical losses because usually there's some difference between them right? And for the sake of semantics do most catalogs offer Ke and Kt with the field...

Still on the matter of windings and so I have some additional questions and I would appreciate your help very much. In this discussion we talked about the effects of adding windings and the pros and the cons of it. If extra windings hurdle the maximum achieved speed why not automatically...

Thanks for all your replies. Some more questions have risen: 1. I wanted to ask seried regarding what you said about always having a pole where the current comes out and another pole where the current goes in. Physically a pole is a pair of wound wire on a metal core, that is one core on one...

thanks a lot everybody

thanks sreid and Bill. two more related questions sreid Isn't the figure for maximum acheivable torque also dictating some speed limits? Bill about magnetic saturation Why and how does magnetic saturation happens? thanx