Dear All,
I faced a strange issue in my shredder suddenly it has been jammed and pended as in the photo by the way my motor is 3KW.
so did any body face such like this issue and how can we improve that.
@davehakkens
Damn, that had to been some force to bent 3+3 mm steel that also was welded.
What where you trying to shredd, @ahmednassar ?
What about autoreverse feature? Like on that video: https://youtu.be/o5sttuCPl_Q?t=99
I don’t know how to do that, but I think it could prevent damage in future.
@ahmednassar
Good catch on the proximity sensor stop circuit, I was about to suggest that.
You could use a little neodymium magnet attached to the shaft and a hall effect sensor connected to an arduino. The arduino can have an RPM counter and if the RPMs slow down too much, it could turn off a relay switch to power off the motor and avoid any damage.
@xxxolivierxxx
@fabirihotmail-com
@ashrak
thanks every body for your valuable information and from my side I made a Root Cause analysis for this problem and after fixing the machine I found these important points:
1- The main cause that the bottom of the PET bottle was too thick and hard so blades was not enough sharp to cut it and that lead to the next point.
2- The blade it self is not made from hard steel to survive with its own sharp edge.
3- The motor was too strong ( 3KW with reduction gear to 70 RPM ) without any safety stop.
4- The overload which is in the motor circuit is not the right one and it needs to be reduces.
So I will do the next steps to eliminate such like this issue to be happened again:
1- I will sort the parts before adding it in the shredder specially the big bottle bottom.
2- I will create a safety stop for the motor contains of a proximity sensor read the shaft rotation with a timer and if it stop reading the timer will stop the motor.
3- Changing the overload with another smaller one.
4- If it is applicable I will change the blades with a hard steel one.
And when I do that I will share the result.
@ahmednassar
3KW equals 4.02HP, assuming your motoreducer had 30RPM it would give you over 900N.m which is an inmense torque for this shredder. If the blades were not properly aligned or if one of them bent and hit one of the fixed knives, then that would explain why your shredder twisted like that. A motor with 300 or 400 N.m would have just clogged but not damaged the machine.
Regards
@ahmednassar Since this topic has nothing to do with modular phones, i moved your topic to – .
Please make sure you post your topic in the right category. Thanks! 
All the best
Flo
Did the rotating blades go against the fixed spacers? If they were no good fixed and they got stuck, with a 3 Kw motor it’s normal you can damage everythink, I think the maximum could be 1500w but I think with 750w it could be enough. by the way if you only was shredding a bottle maybe the blades were no fixed welland move against the spacers.