Siemens Ladder Logic Programming Help Needed.

[viviathevan]

lancie1, i have implemented ur idea by using one push button for the flushing system. thank you so much.

 

[viviathevan]

My full programming. please check.

My full programming is attached here. please do check for me if i did any mistakes.

And please do advise or correct me. thank you so much. looking forward for your reply.

 

[moggie]

My full programming is attached here. please do check for me if i did any mistakes.

And please do advise or correct me. thank you so much. looking forward for your reply.

Network 2 Remove the "LID_solenoid" Q0.0 contact - else the nutrient to water can only work if the LID is open!!

Network 2 You have used a contact of "Stirrer" Q0.3 but I cannot see the output programmed anywhere in your program?

Network 3 Remove the "LID_solenoid" AND "Sol_nut_to_harvest" contacts - else the "water_ready_to_use_indi" will not indicate correctly.

Network 4 You have used a contact of "Sol_nut_to_harvest" contact - this should be a closed contact (or remove it completely)!

Network 5 You have programmed a Timer - T37 But I do not see it used anywhere?

Network 7 This is incorrect you have already programmed these outputs in network 3 & 6.

 

[viviathevan]

As for the Network 2 and network 3, I did put the previous output as my input to the network and continue it as to network 4 because I did ask one of my friend and she said that the process is one after the other, so you have to include the output of the first network to second network and so on. So that it will work as an sequence.



I did two programming as well. One is by the way she thought and one is the way by the people and you thought me how to do. So I will stick to this programing method where i do not to make it like an sequence.





yes in network 2, i have put the stirrer as an input and not as an OUTPUT!! ( silly mistake done)



For network 5, yes i have programmed it and i "Forgot" to include it in network 4.



For network 7, i really dont know what i did. thats why i asked your help.



This is what i realize from the mistakes i done. THANK you so much for correcting me.

 

[Lancie1]

Vivi,

Some more comments on your "My Programming.pdf" file:

1. In Network 1, you have a PUSH_Start I0.6 to "Start the whole process". Good idea, but you must know WHAT this Start button is and how it works. If it is a normal, standard, momentary-contact push button, then your Network 1 will not work very well. You will have to stand there and hold your finger on the PUSH_Start button to keep things running. I bet that that you did not see yourself spendig a lot of time holding your finger on a button!

On the other hand, if you have a Push-to-Start, Push-to-Stop button, you are okay. If not, you need this additional logic in a new Network 1 (insert it in front of the old Network 1).

Tip: If you ZIPPED (compressed your Siemens program with WinZIP or similar program) and posted the ZIP file here, then people could add changes directly to the program instead of having to describe them to you.

New Network 1 (for standard momentary-contact push button): see attached picture.

 

[Lancie1]

Vivi,

This is how I would change your networks. I added a RUN relay that can be used on every rung that needs to shut off when STOP is pressed. Use the same button to Start and Stop. Press once to start, press again to Stop the system. I also cleaned it up, fixed the timer, and other things.

 

[Lancie1]

Vivi,

If you use the copper electrodes for pH sensor, then you need to reverse the polarity of the I0.3 pH Sensor instructions in Networks 3 and 4 - from NC to NO in Network 3, and from NO to NC in Network 4 (see attached Revision 3). This is because the pH Input will be OFF until the water goes below neutral pH. So in Network 3, you want the Solenoid to be OFF until the pH Sensor goes ON, and vice-versa for Network 4.

If you cannot read the labels, you may need to ZOOM in your screen temporarily.

 

[viviathevan]

Power supply connection!!!!!!

Hello there, i am using a siemens cpu 212 plc.

I am really not sure where to connect the voltage supply for my PLC. Can anyone just help how to connect the PLC with power supply. Please do attach some images or something.
Thank you.

 

[moggie]

Hello there, i am using a siemens cpu 212 plc.

I am really not sure where to connect the voltage supply for my PLC. Can anyone just help how to connect the PLC with power supply. Please do attach some images or something.
Thank you.

Here is the link to the S7 200 System manual - all the information you require is in the manual
http://support.automation.siemens.com/WW/view/en/1109582

 

[Lancie1]

Moggie,

Unfortunately, that manual will not help very much, because it is for the later models 222 and up, where Vivi has the S7-212. Here is a picture of the wiring for the S7-212 Model 6ES7-BA01-0XBO, with changes marked in red to add the pH Sensor to Input I0.3. The other inputs for the Rain Harvesting project would be wired to the remaing inputs 0.0 thru 0.7, and all should use the built-in 24 VDC power supply to power the inputs.

EDIT: If the only manual you can find is the newer version, then your S7-212 has the same wiring layout as the newer S7-222 model 6ES7-1BB23-0XB0 shown on page 402 of Moggie's Siemens link.

Here are links to Vivis two other threads on this same project: http://www.plctalk.net/qanda/showthread.php?t=69735&page=5
http://www.plctalk.net/qanda/showthread.php?t=69945

 

[moggie]

Moggie,

Unfortunately, that manual will not help, because it is for the later models 222 and up, where Vivi has the S7-212.

Lancie1
Sorry for posting wrong link - this is the correct one

http://support.automation.siemens.com/WW/view/en/1109154

 

[viviathevan]

Thank you lancie so much.

Actually you are guiding me alot every time.

Thanks a lot also to moggie. You are the one who helped me not my lecturer. Thank you so much.

 

[viviathevan]

i have a question here.. i dun knOW what type of power supply can be given to my PLC.

any type of power supply ( 24 V DC) will be okay right. should i see the current as well.

my model is siemens cpu 212 6ES7 212 1AA01 0XB0. please help.

 

[Lancie1]

Any type of power supply (24 V DC) will be okay, right? My model is a Siemens cpu S7-212, Model 6ES7 212 1AA01 0XB0. Please help.

Vivi, Wasn't it kind of dumb to post a picture of a Siemens 6ES7-BA01-0XB0 in your Post #53 (which requires an AC power supply) when now you say you REALLY have a 6ES7-212-1AA01-0XB0 (which requires a 24 volt DC power supply)? All your posts together make me think that maybe you might be a high-school student working a little over your head?

Oh well, if you weren't a beginner, life would be less interesting!

No, any type of 24 VDC power supply is NOT OKAY. Size does matter. You need one large enough to do the job. The way you should do it is add up all the current loads on your Rain Harvester, then multiply by 1.25, and buy THAT size. Yes, you should "see" the current as well. You should try to buy as large a 24 volt DC power supply as your budget will stand. The larger, the less chance of overloading it, but also the more it will cost. Try to buy at least a 100 VA, 4 or 5 Amperes at 24 VDC, 24 volt DC power supply, that will plug into and run from your local electric utility residential power.

 

[viviathevan]

Connecting input and output terminals in my plc

i have bought a power supply with 5 A current rating and 24 VDC power supply. now i am having difficulties in which hole i need to plug in. i have a picture on how to connect the input and output but in case for safety and to confirm i am asking again. please do help me in it.


let say all my inputs and outputs have two terminals positive and negative. which one wire i should connect to the I0.0 or Q0.0. the positive or negative or either one wire because there is no label.( in some device).

i hAVE MANAGED TO CONNECT THE POWER SUPPLY AND THE PLC IS IN ON STATE.

Please guide me how to connect the i/o devices as well. Thank you so much.