I also have a bad experience with Aliexpress.
Ordered 5 motors 12 watt BLDC geared motors at topbrand via Aliexpress (95$ a piece exclusive postage). They were advertised as standard out of stock motors.Quality of the product
Got only 4 (they keep the money for my next buy
) because they only made 5 and killed one.
You have 2 wires for power 24 V, 1 wire for speed (PWM 5V) and 1 wire to connect to ground to change the direction (but not 5V resistant)
on one of the motors the PWM and direction are switched => 5V on direction => another motor dead.
So 5 motors mode only 3 survived the first run.About quality of service:
I send the money on the 16 th of januari (no paypal or visa)
They confirmed receive of the money on 9 feb (due to chineese new year
They send the motors on the 4th of april (that is about 2 months to ship the products)
The motors arrived the 14th of april.
So 3 months to send 3 working motors of an order of 5 where I need 4 of them. 600$ down the drain About service after delivery:
Normally they are very responsive but since I reported the dead motor (with picture of the internals to prove the bad connection): Not a single word.
I have plenty of good experiences with chineese companies but this is way over the top.
It even got worse.
I attached the 2 motors to my robot and .... nothing happened.
I tested the torque and the torque is 0.5NM where the spec of the motor states 2NM.
I had to make a movie to show that the motor simply can not lift more than 0.7KG with a wheel of 0.2m wheel.
The response op topband is even more baffling than anything else I heard from them. I quote:
controller engineer told me that this motor is without hall sensor, which means if the motor works with higher loading, it will work bad.
usually, the non- hall sensor brushless motor is loaded with a fan or blower which is not big.
you can't always complain our motor, I think you also should consider other possibilities.
So I give them my specs for a driver motor.
Voltage up to 29V (battery fluctuates between 29V and 22V)
Driver can be any voltage. Already available are regulated 5V 12V
Stall torque at the wheels should be minimum 8.9NM
rated torque at the wheels should be minimum 1.5NM
rpm at the wheels should be minimum 61
The output watt at the wheels should be substantial above 15
They propose this motor and now it is all my fault ......
So this 95 USdollar motor has a torque of 0.5NM at a RPM of 61. I seriously got ripped off.
My conclusion: stay away from topband.