Micrologix1000 Output To Timer

Shanntman

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Feb 2020
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Working on a machine that uses an Allen Bradley micrologic’s 1000 controller. Wondering if there is away to tie in the output to an external counter & time delay relay. The output powers a 24 V solenoid but I need it to be adjustable..Been playing with it all night.
I’m used to the click PLC and never really understood how Allen Bradley has 24 V going to a solenoid when output is off? And 0V when the output is on? Seems pretty controversial..Unless it’s NC circuit but someone please correct me if I am wrong?

Thanks
Levon
 
Working on a machine that uses an Allen Bradley micrologic’s 1000 controller. Wondering if there is away to tie in the output to an external counter & time delay relay. The output powers a 24 V solenoid but I need it to be adjustable..Been playing with it all night.

The cleanest solution would be to put the timer and counting functions inside the PLC but that will require programming software and some know-how. You should be able to add an external timer to the circuit but there are some considerations, like adding to the load handled by the PLC output point and how to wire the timer so that your intended result is carried out. Two of these considerations are:

1. What happens to the PLC logic if you cause a delay that affects another part of the machinery reaching a certain input for example.
2. What happens if the PLC input turns off before your delayed action is completed?

Can you wire the timer in such a way to keep the machine working properly?

I’m used to the click PLC and never really understood how Allen Bradley has 24 V going to a solenoid when output is off? And 0V when the output is on? Seems pretty controversial..Unless it’s NC circuit but someone please correct me if I am wrong?

Thanks
Levon

A voltage measurement is simply a difference of potential between two points. What are the two points of reference you are using for this reading? I could guess about 3 different scenarios that could seem "backwards" as you report.
 
You make a good point with the PLC logic, however I assumed I would use the output to start the timer, feeding the solenoid power through the coil. Thus, not changing the real time value that the output is “on” through the PLC. I’m fully capable of wiring it in that manner and did have it running but seems it is effecting the cycle of the machine somewhere along the way. Although I don’t see how because it is just a solenoid to an air cylinder which does not have any switches or functions other than retracting for a sufficient amount of time to allow bottles pass by on a conveyor.

I’m almost certain it is in relation to the connection to that input. Either a different load now that you mention it, or feeding power to the output? That is what confuses me..If the Output is off and I test across O/4 and it’s common, I’m getting 24V. However when output is “powered” it changes to 0V. (This goes for all Outputs on the module) inputs on the other hand read 24v when a switch closes as they should. I’m not too familiar with AB controllers but I have noticed many function this way, just trying to figure out how exactly that is.
 
Sounds to me like you have sinking outputs - not sourcing outputs


Are you familiar with these terms?


Are you using the same "common" for both inputs and outputs?
 
Outputs

As a matter fact their sourcing outputs which is why it’s confusing to me.

I’ve been giving this some thought and given the program currently in the PLC technically it should not allow the solenoid to stay on longer than another cylinder with a reed switch, which is exactly what I am trying to do. I’ll see if I can upload a video of current operation and will upload a pic of the ladder logic if that helps. I did consider going into the program but I’m trying to avoid opening up a can of worms.
 
If the Output is off and I test across O/4 and it’s common, I’m getting 24V. However when output is “powered” it changes to 0V. .

If you are measuring the Common (power input) terminal on the outputs terminal strip those readings are correct. With the output open there is a 24V drop across the open relay/transistor, and 0V when the relay is closed.

Read the output to 0V somewhere on your panel, or the 0V common to the inputs.
 
Current Program Running

This is the operation of the current program. Since then I install the counter so cycle will not start until 2 bottles are present. Once the nozzle rack rise back into normal position I need the left cylinder to stay out in order to prevent bottles from entering the filling station and the right cylinder To attract for a set period of time allowing bottles to pass and keep traveling down the conveyor. I’ll upload pictures of the program if anybody would have a simple way to do this possibly an up count/down count? However as I said I’m pretty good with click programming but I’ve never programmed Allen Bradley PLCs before so if it could be done externally all the better.

Copy & paste:

https://drive.google.com/file/d/1Nh8v4mL8fmoMbgT9x9nmlJxflOXGF4Xj/view?usp=drivesdk

Let me know your thoughts.
 
Ladder Logic Program

So this is the current program. Basically what I need to accomplish is to extend time if O/11 (Left Cylinder) allowing O/4 (Right Cylinder) to stay on for a few seconds. Then reset which I can handle....Any ideas?

4BE86500-D379-4A88-A6EE-2D93F0796126.jpg 29FC46A9-9E0D-4322-A468-B12F4F447DA1.jpg 4B222AEE-7681-49DF-BF8D-D46147889631.jpg B5C0D598-3024-4C3C-BF0C-87E3662CFF45.jpg 16BAEB41-E628-4353-9701-D677E5A95AB0.jpg
 
I believe the free version of RSLogix Micro Starter edition will allow you to program all Micrologix 1000 models as well as certain Micrologix 1100 models. I only opened one of your pictures of the logic printout, but if you could get set up to program the PLC, you will have a much cleaner end result and expand your skill set along the way. If you are comfortable with the Click, you will like RSLogix, although the ML1000 models are very limited.

Here is a technote (registration required) Access Level: Everyone:
https://rockwellautomation.custhelp.com/app/answers/detail/a_id/63956

That explains how to locate and download the free version.

Then you'll probably want to get a cable from:
https://www.plccable.com/allen-brad...2-si-series-micrologix-plc-cable-programming/

That one is short but works well with his USB-RS232 converter which is plenty long:
https://www.plccable.com/industrial-usb-rs232-usb-serial-plc-programming-w7-xp-rs232/

THEN you could upload the code, or open the file with comments (unlike the Click, there are no comments stored in a Micrologix), save a documented file, zip it and share it with us, and we can have your changes sorted out quickly and and future mods you might need will be easier too.
 
Okie

👍 Great- Thank you Okie. I did get it working with an external counter and time delay relay, there is a reed switch on the 1st cylinder that was not allowing me to power the right without the first retracted...Jumped it for now but still not happy with the result. I’d love to dive into the Programming but just don’t want to open up a can of worms...I know AB is much different than Click. Was a hair away from ripping this out about an hour ago and just installing another PLC but if I can get the AB program to work that would be fantastic.

Here is a video of proper operation:
https://drive.google.com/file/d/1yU-mjaoCy_b_3_0cf4twH22ehxlQyNp8/view?usp=drivesdk
 
So this is the current program. Basically what I need to accomplish is to extend time if O/11 (Left Cylinder) allowing O/4 (Right Cylinder) to stay on for a few seconds. Then reset which I can handle....Any ideas?

Looks like O/4 is your "star wheel" not your "right cylinder"

Paul is right, the Micro software that he linked is free and will let you program any 1000 or 1100, if you upload the program and post it we can help more, its just hard to read the sideways printout

This is a good cable for you to upload https://www.plccable.com/allen-bradley-usb-1761-cbl-pm02-for-all-micrologix-plc-communication/

And thanks for the plug's Paul
 
Yes correct it was previously set up as a star wheel solenoid but this is much more versatile going to download program and play with it a little bit I just didn’t want to dive too far deep into the logic to where I can’t come back...Never programmer AB before, just KOYO

Thank you though much appreciated
 
I just didn’t want to dive too far deep into the logic to where I can’t come back...Never programmer AB before, just KOYO

All PLC's are the same... they take a input and decipher some logic and make a output, they just may do it a little different but that Koyo will make a cylinder extend just like the AB

First thing, upload the program and make a copy, put the copy in a safe place and if you have issues and screw something up you can ALWAYS go back to square 1 and start over, we all have made programs/machines worse before they got better
 
..Never programmer AB before, just KOYO

I have found a good knowledge of ladder logic works across many platforms. ST too.

With extensive AB and Siemens experience the first time I opened Panasonic NAIS, Mitsubishi GX Developer, Omron Syswin and others the only thing I had to "learn" was how to pick the elements in the programming software I wanted and the addressing of the IO, bits and words. Once in a while there is a strange way of doing something (Omron's OneShot XIC's have to be set beforehand then XIC automatically turns into a OSR) that isn't readily recognized, but not too often.
 

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