How to connect AB Micrologix 1100 to a Brush-less DC Motor

[chase_yq]

Hi, Everyone

I am a beginner to PLC. I am currently working on a project to build a door cycle tester.
Allen Bradley Micrologix 1100 is used to control a Bodine 34B/FV Brushless DC motor. Then this motor drives a shaft system to open/shut the door at certain speed. The final goal is: 1. I am able to set a certain number of cycles then the device will execute it. The values of cycles can be displayed on LCD of AB Mircologix 1100.

My current problem is the motor cannot even be driven by the AB 1100.
This could be an issue of wiring or programming. However, I could not figure it out on my own after lots of tryouts. The code I wrote was just a single rung (closed contact as input, Motor Forward/Reverse as output). Again, it was not working.

I have attached an document here which provides more details of the wiring as well as the programming portion.

I sincerely wish someone could offer me some help. Thanks to all of you.

 

[Levi G]

I don't know much about running brushless motors but input 1 is not true (closed) and you are only closing output 1 you also need to close output 0. and polarity on dc motor is backwards.
Edit:input 1 is ok

 

[gclshortt]

I would wire this up manually as well so you can prove that the motor is working correctly. Then add the contacts from the PLC to control automatically.

Regards,

 

[jkerekes]

A silly question: Is it in RUN mode?

 

[chase_yq]

Yes. it was in run mode.

 

[amberman]

Yes. it was in run mode.

Levi gave you the answer above. Just closing O/P 1 will do nothing, you need to close O/P 0 too to connect the 24V supply to the motor.

 

[chase_yq]

The motor is working perfectly.

 

[bernie_carlton]

Your output wiring as shown will not be sufficient to achieve a Forward/Reverse control on the motor.

And, as others have pointed out, with this wiring you have to energize both outputs 0 and 1 to connect the motor to the supplied power.

If I were designing this I would use two external relays. One larger for switching power On/Off. Another would be a 2P2T relay for direction switching. This arrangement would avoid switching motor power through PLC contacts.

 

[chase_yq]

Thanks for your answer. This DC motor come with a quadrature encoder. Is there anyway to control motor to turn forward/reverse with encoder?

Thanks,

 

[bernie_carlton]

While the encoder will give you INPUT information to determine which direction the motor is moving it does not actually control that movement.

 

[Dravik]

That motor requires a PWM input to set speed...(So you shouldn't be trying to bring PWM in to the PLC, you should be using the PWM function to output back to the motor)

 

[Dravik]

To drive the motor at max, supply the PWM pin w/ straight 5v.
Edit - This assumes the PWM input is Active High... If you specced it active low, jumper it to ground to drive the motor at max.

 

[Firejo]

What does the teacher teaching the class say?

 

[bernie_carlton]

Ah, Dravik must have read the motor manual. No fair. We love having to guess.

chase_yq - time for you to read the manual also. Good luck.

 

[Dravik]

Ah, Dravik must have read the motor manual. No fair. We love having to guess.

chase_yq - time for you to read the manual also. Good luck.

Guilty as charged!