Shohadawy,
What they are trying to say:
1. Normally, a 3-phase industrial motor is NOT connected directly to a PLC. If you want to control the speed of a 3-phase motor using a PLC, you must have some additional equipment, such as a Variable Speed Motor Drive.
2. You may have an instructor that has some type of small toy motor that can be connected in some fashion to a PLC, but this is not very useful in the real world. If that is the case, you should know that it is only for experimenting and has no useful function except for learning about PLCs.
What they are trying to say:
1. Normally, a 3-phase industrial motor is NOT connected directly to a PLC. If you want to control the speed of a 3-phase motor using a PLC, you must have some additional equipment, such as a Variable Speed Motor Drive.
2. You may have an instructor that has some type of small toy motor that can be connected in some fashion to a PLC, but this is not very useful in the real world. If that is the case, you should know that it is only for experimenting and has no useful function except for learning about PLCs.