Control a DC motor using PLC

Hello

I hope you are all well and safe

I am not experienced with PLCs yet and I need help.

I have a plc ( s7-1200/1500) and I would like to control a DC motor to lift and lower a weight ( same weight ) ,
so for lifting the weight. I need the plc send a specific speed or torque to motor or the motor drive
for lowering, I want to control the motor with torque/speed enough to lower the weight.

it is my first time writing a thread, I still find it hard to explain my objectives ( I apologies ), but if you do understand this thread, plz I ask for your guidance.

P.S: the motor's Torque is High enough to lift the weight

to make it simple, I need help to control a dc motor speed and torque using a plc or motor drive

Thank you
be safe
 
Welcome to the Forum.
I'm tempted to say the PLC is the easy bit although as a beginner, Siemens PLC's take a little time to understand.

You haven't stated make/model of motor drive, so I'll make a few assumptions:
For raising, you want the PLC to give a digital o/p (output) to 'Go!' {upwards} with a simultaneous analogue signal to the motor drive of torque of sufficient value to overcome gravity. On removal of the go signal the motor stops, but more appropriate the drive has some form of brake to prevent reverse {downwards} motor movement.

For lowering, you want the PLC to give a digital o/p (output) to 'Go!' {downwards} with a simultaneous analogue signal to the motor drive of torque of value to give slow descent speed to prevent runaway.

To achieve the above, you need to be certain the motor / motor drive will not only provide torque for ascent, but braking torque for descent. Maybe also an electro-mechanical brake which could be activated from the PLC.
 
It was a few years ago but I had a project with a Siemens S5 (it was a few years ago !) using Emerson drives.
The only digital signal was a 'stop' signal for safety reasons. All the commands, including stop, were sent by ASCII messages to each drive {four in total}. Made the Software an interesting challenge !
 
Welcome to the Forum.
I'm tempted to say the PLC is the easy bit although as a beginner, Siemens PLC's take a little time to understand.

You haven't stated make/model of motor drive, so I'll make a few assumptions:
For raising, you want the PLC to give a digital o/p (output) to 'Go!' {upwards} with a simultaneous analogue signal to the motor drive of torque of sufficient value to overcome gravity. On removal of the go signal the motor stops, but more appropriate the drive has some form of brake to prevent reverse {downwards} motor movement.

For lowering, you want the PLC to give a digital o/p (output) to 'Go!' {downwards} with a simultaneous analogue signal to the motor drive of torque of value to give slow descent speed to prevent runaway.

To achieve the above, you need to be certain the motor / motor drive will not only provide torque for ascent, but braking torque for descent. Maybe also an electro-mechanical brake which could be activated from the PLC.
Yes, it is exactly what I wanted,
for the motor drive, I found a 50 Amp one ( SyRen Single 50A DC Motor Driver ), since I will use high torque 24v gear motor ( max 40 amp ).
I do have a brake to stop the weight at a certain position, I can also use an electromagnetic brakes/clutch.

Thank you,
have a nice day.
 
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