can not turn on the motor with PLC

the N.C. contact with wire coming from the PLC output looks like a Thermal OL. The Plc output is connected to terminal 95 on thermal OL and the wire going to A1 of your motor contactor is on terminal 96 of the OL. This would explain why it works when manually pushing it in. Try Resetting the Overload. Or at least measure voltage at terminal 95 to see if you are getting voltage from the PLC. Also are your outputs Fused?
 
Nevermind, I just read through the post and seen it's working by manually activating the contactor. I didn't see the diagram of what energizes that contactor. do you have that available?
 
I would Verify the actual Contacts on the E-stop PB are N.C. being that is the only thing that turns CR60044. Couldn't tell you how many times wrong blocks were put on buttons
 
If this is an actual motor starter and he is pushing in the contactor with the starter door open I hope he has the proper arc flash rated clothing on. I would not make manually pushing the contactor in a common practice.
 
I would Verify the actual Contacts on the E-stop PB are N.C. being that is the only thing that turns CR60044. Couldn't tell you how many times wrong blocks were put on buttons

So what I am trying to do here is, Turn On motor with PLC code So i download my program and press the start button to turn on motor and I see my output bit of motor in PLC become 1 but my contactor is not energized which means current is not flowing from output card to contactor but Is there current at output card? No there is no current on output card because when i test there is no voltage.
How my output card getting voltage? its getting from Control relay and control relay is enegrized by E-stop

What I need to do now is, want to check if I am getting voltage at input of CR which is from Estop and Voltage at Output of relay which is going to Output card of plc.

Then I can figure out whats the issue

But when I manually press that Control relay, I can see current on my output card and It pass to contactor and motor gets turn ON.

Motor gets ON in two condition

1. manually press of Control relay
2. Manually press of contactor

Any idea? What do you think what could be the possible issue?

Thank you again,
 
If this is an actual motor starter and he is pushing in the contactor with the starter door open I hope he has the proper arc flash rated clothing on. I would not make manually pushing the contactor in a common practice.

Ok, may be you are right but I am not electrician :/
 
I hope you check this already, it a common mistake by novice,
Check that the 0V of the contactor and output card are connected to the correct reference source.
 
Please check this link

https://ibb.co/nr2Okb

Can you please explain me what is this? When I puss this to 1, then my PLC code work and it turn on the motor. how can I pull in with PLC code?

I think my NC estop energizing this device? i guess? Because there is label on this device CR60044 AND in my electrical diagram, e-stop energized this coil

I'm going to guess that the picture shows an MCR of some sort. You would need to look at the prints/program for the entire cabinet to know what is supposed to pull that relay in.

It made me laugh when you said the electrician shoved the starter in and the motor ran. My guess is that they then told you that it's not their problem, and walked away. The best advice I can give you is to find out what kind of doughnut the electrician likes best, and make sure there are at least 3 of those in the big box of doughnuts you bring in for all the maintenance people. The problem you are having is troubleshooting 101, and the fact that the electrician isn't helping you is a good indication that you have either failed to impress, or worse yet pi$$ed them off. You need to make peace with the electrician. Free food for them and their co-workers is a good place to start. Also apologize for how you have acted, even if you have done nothing wrong. You are very new to this field, and so far haven't earned the respect that more experienced programmers/engineers would get. So you need to buy/bribe their pity and convince them that you deserve to be helped. Free food and a show of respect might just get you out of this jam.


Bubba.
 
I'm going to guess that the picture shows an MCR of some sort. You would need to look at the prints/program for the entire cabinet to know what is supposed to pull that relay in.

It made me laugh when you said the electrician shoved the starter in and the motor ran. My guess is that they then told you that it's not their problem, and walked away. The best advice I can give you is to find out what kind of doughnut the electrician likes best, and make sure there are at least 3 of those in the big box of doughnuts you bring in for all the maintenance people. The problem you are having is troubleshooting 101, and the fact that the electrician isn't helping you is a good indication that you have either failed to impress, or worse yet pi$$ed them off. You need to make peace with the electrician. Free food for them and their co-workers is a good place to start. Also apologize for how you have acted, even if you have done nothing wrong. You are very new to this field, and so far haven't earned the respect that more experienced programmers/engineers would get. So you need to buy/bribe their pity and convince them that you deserve to be helped. Free food and a show of respect might just get you out of this jam.


Bubba.

HAHA I agree with you and Estop is hard fired and I should not be controlled or stop the circuit with PLC and after doing some research and reading electrical drawings, I am getting close to and trying to understand. This is what I am getting so far.

1. There is E-stop which energize the Estop Relay/ Control Relay (CR60044) all the time and my armature coil should be 1 all the time.

https://imgur.com/a/WQqbX (This electrical diagram say, Estop is Normally Close and energize the Control Relay (CR60044)

But In my case, when Estop is not pressed, which means E-stop is normally closed, my Control relay is de-energized but it should be energized.

I need to figure out why!!!
 
You are missing the trees for the forest. Take each part on step at a time. Ie; Do you have power in and out of the e-stop? Is there power to the coil of the contactor? Use the prints and check one thing at a time starting at the power supply until you find where you should have and don't. Then it should be easy work to figure out why.


Bubba.
 
EStop buttons are supposed to be NC, not NO, so that pressing them breaks electrical continuity. If you only have power to the relay (and therefore the ability to start your motor) when the EStop button is pushed, then that is the source of the problem.

If the EStop is not allowing power to your relay, then you don't have a circuit from your PLC output through the EStop relay to your motor starter and to your common, so you won't see voltage on the output. Is that the case?
 
EStop buttons are supposed to be NC, not NO, so that pressing them breaks electrical continuity. If you only have power to the relay (and therefore the ability to start your motor) when the EStop button is pushed, then that is the source of the problem.

If the EStop is not allowing power to your relay, then you don't have a circuit from your PLC output through the EStop relay to your motor starter and to your common, so you won't see voltage on the output. Is that the case?

LoganB, I agree with you the Estop button has to be NC for safer circuit and in case of wire broke while machine running and when someone presses the button, it becomes NO and breaks the electrical continuity.

In my case, First of all, I don't know why Estop is spring return which means even though if its NC Estop and someone will press that Estop and leave it, it will come back to NC state again because of spring loaded.

Now, I tried to hold the Estop but I still can't energize my Estop safety relay, the device I asked you earlier is safety relay. Means, Any condition of Estop does not energize my E-stop/Control relay.


So I believe Estop circuit is not complete or wrong that's why Control relay does not energize in that situation.

https://imgur.com/a/WQqbX

Now, I am trying to explain the same thing to my maintenance guy and he is like no its PLC issue nothing wrong with the circuit.

Just wondering, what do you think about it? what's your thought on it.

Thank you again and sorry if i am bugging you.

Thanks
 
EStop buttons are supposed to be NC, not NO, so that pressing them breaks electrical continuity. If you only have power to the relay (and therefore the ability to start your motor) when the EStop button is pushed, then that is the source of the problem.

If the EStop is not allowing power to your relay, then you don't have a circuit from your PLC output through the EStop relay to your motor starter and to your common, so you won't see voltage on the output. Is that the case?

Also, I have a power supply goes to Estop and then the output of estop is going to control relay to energize that relay and then the output of control relay is going to output card of my plc and In case, someone will press the Estop I should de-energize that relay and output card will get 0 voltage and I guess this is how Hard wired Estop works. Correct me if I am wrong.

Thanks
 

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