Starting Time For Conveyor/Crushers
Starting Time For Conveyor/Crushers
(OP)
For a lime stone crusher and conveyor, what is the typical starting time for thier associated motors assuming these equipment are being started with load on them.
We have not received the torque and current vs speed for the motors and torque vs speed for the load and associated equipment and motor inertias. Therefore, a feedback from an experience fellow will be greatly appreciated.
We have not received the torque and current vs speed for the motors and torque vs speed for the load and associated equipment and motor inertias. Therefore, a feedback from an experience fellow will be greatly appreciated.






RE: Starting Time For Conveyor/Crushers
RE: Starting Time For Conveyor/Crushers
Loaded restart on a rock conveyor is also very problematic, it depends on the angle, the length, width and load depth and the weight. There are no simple answers. Your OEM may have selected motors based on a specific performance criteria, if that didn't include loaded restart, it won't be capable of it. Most will not unless specifically instructed, it means seriously oversized motors which drives up the price.
As a very general rule regarding standard motors though, start times in excess of a few seconds require very careful engineering. You can do whatever needs to be done, but you really need to determine what you want to accomplish before you pick the motor.
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RE: Starting Time For Conveyor/Crushers
The fuse sizing is just preliminary to get some stocks reserved and we will later finalize after we get OEM response (hopefully quick).
RE: Starting Time For Conveyor/Crushers
Generally they are selected to allow the motor to supply FLT + (potentially up to break down) by allowing the motor to run at rated speed prior to application of load.
If this is the case, then the starting time could be calculated using a=T (motor torque)/I (motor plus motor side of fluid coupling).
You can time step using Excel to calculate accurately, though if you have equivalent circuit of the motor you can calculate exactly, if you choose.
If you calculate neglecting the fluid coupling / assuming standard DOL, suspect you will have limited capacity to start the crusher (i.e. only FLT or slightly above cf up to breakdown) availible during the start.
RE: Starting Time For Conveyor/Crushers