PLC Advise for Simple Process

[Derek K 0]

I'm looking to buy a PLC off of Amazon as well as 2 relays (possibly with timers).  I'm new to PLC design and programming.  Some of the PLC's on Amazon com come as a complete kit with software, cables and the PLC itself.  

I want the PLC to engage both of the relays for a controlled length of time (approximately 45 Seconds).

Essentially I want to push a button and a weld positioner will start to rotate and a weld gun will start welding.

Does anyone have any suggestions on which (Cheap) PLC to purchase as well as relays on amazon? Anything else I need?  How do you power a PLC?  I would love to just plug it into a 110v, AC outlet but I'm not seeing any options for this.

 

Thanks in advance!

20231011141325739.pdf

[Joe E. 259]

Check out Automation Direct. You can get a Click PLC (free software download) with on board Ethernet and IO, with a power supply for about $250. They also carry relays (I've had very good service from the Klemsan slim line relays, $8/each).

How much do you know about wiring relays and such? If you download the manuals for the Click and the software, you can try it out to see if it will work for you.

Edited 12 Oct 2023 by Joe E.

[Joe E. 259]

Another thought. For something that super simple (and if you KNOW that it'll stay that super simple), you could just use a timing relay. This guy, for example, will probably do that in "single shot" mode. I'd have it drive other relays, though, instead of the loads directly.

[Derek K 0]

Hi Joe - Thanks for the response and advice.  I know nothing about wiring relays - this is my first attempt at this.  Approaching this with the Crawl, Walk and Run mentality.  Hoping this forum will help guide me as well as other online resources.  

If you know of any good beginners videos, websites or other literature - I would love to hear about them as well.

 

Thanks!

[Joe E. 259]

For PLCs, I'd start by going to YouTube and searching for Ron Beaufort. The videos are a little dated and are recorded using older AB hardware but the concepts are sill extremely valid and useful.

What's your electrical/electronics background? If you download the datasheets for the PLC IO modules and the relays, can you figure out how to wire them together?

[BE 13]

Based on your schematic, I would second what Joe said about the timer. Unless there is a reason to use a PLC (ie. future changes to the design that we don't know about), then a timer will work fine, and be the simplest option.

I don't have any experience with cheap PLC's as such (all my experience is with Omron), however the job you want to do could be done quite easily with an Arduino microcontroller and a couple of relay modules. Quite cheap, programming software is free and there is a bucket load of sample code for various things available on the internet. The code itself isn't the easiest to learn if you have absolutely no coding experience, but this is offset by the tremendous amount of free resources, videos and forums dedicated to Arduino programming, with plenty of people willing to help you, if you are willing to have a go first.

Not sure what costs are in the USA, but for me in Australia, setting up something like you describe would cost me less than $50AUD, depending on exactly which Arduino board I went for - and to the best of my knowledge any Arduino board would do what you want, as you only have 1 input and 2 outputs.