Can a PLC act as a web server?

[flugelizor]

I just had a visitor view my E-panel. He is looking to do similar in a college class.

I have a 50 amp box with SSRs and contactors, and a BCS-460.

So he looks at it all including the BCS java page, and says "oh that's easy, a PLC could take the place of the BCS" ?

Is that right? Can a PLC run a java app, save config info, essentially act as a web server?

 

[SoCal-Doug]

Some can, some can not. Most PLC's can define, save and recall configuration data, this is very common where they are used. Some can read and write XML (i.e. beersmith files) and can have a web based interface, if you really want to work that hard. A good PLC with UI, networking, analog and digital I/O is going to be costly compared to a few PID's or a basic microcontroller based brew controller, although PID and process control logic blocks are pretty standard now in PLC's. It's also going to involve configuring and coding. Out of the box, they don't do a thing.

We use Allen Bradley and Siemens PLC's on our automation designs at work. We've also used them for medium scale commercial breweries. They would definitely make for a fancy brew controller but this engineer opted for a couple PID's on his home rig. Unless its for money, bling or just to nerd out because you have the time and extra cash to play, there's really no reason to go that nuts. It's not going to make better beer or save you any time on brew day.

 

[flugelizor]

Well, I learned something. I knew a raspberry pi could do it, but, that's news. Tech is cool.

I am an engineer by education, software developer by trade, and when I saw the BCS, I said to myself- way more cost effective to buy, rather than code.
No, I don't work for them.

 

[SoCal-Doug]

[Topically speaking] A PLC is really nothing more than an SBC running low level scripting and logic blocks. You define the gazinta's and gazouta's for the application and plug in the hardware you need (maybe an analog input module, network module, or digital output module. most have a few channels built in but never enough without buying add-ons). Create some logic and ties with a graphical interface, and bring in the blocks and functions you need (or hand code them if they aren't in the library). Small blocks come together to make bigger blocks, and so on. Drag and drop like a schematic editor, test, then compile and upload to the device. A little like a very crude version of visual studio, but runs in near real time without windows $hitty timeslicing and no buggy .Net libraries or kernel to deal with. Definitely many steps above and much easier than writing C or assembly code for an 8051, microcrap, or ARM processor.

 

[Inspire]

So he looks at it all including the BCS java page, and says "oh that's easy, a PLC could take the place of the BCS" ?
Is that right? Can a PLC run a java app, save config info, essentially act as a web server?

Very expensive. I've looked into it. My Friend got me a quote and was about AUD $3,000. I think the basic model was $300, but it was just a dumb unit and for it to be web server, you'll need upgrades. There's lots of types of PLC, and different companies with their own propriety PLC, and the basic DON'T have web server. You'll need addons or higher models.

PLC are just dumb unit. You upload your program to it and it does your program. For web server stuff, you'll need upgrades and that's costly.

But PLC is industrial grade, so highly reliable...but comes at a high cost.

 

[clearwaterbrewer]

Red Lion comes to mind... couple hundred bucks if you get it right on eBay...

http://www.redlion.net/product/csmstrgt-data-loggerweb-server-virtual-hmi-vga

video of HMI:

 

[Merak5]

Anybody look into the Rockwell Micro 800 controllers?

 

[Inspire]

This was my quote in September 2017 from Unitronicsplc. My requirements was:
Following are our requirements for the PLC/HMI Vision 350:

• HMI size: 3.5'
• PLC IO count:
  • Digital Input: 4
  • Digital Output: 17
    
  • Analog Input: 6
  • Analog Output: 0
• Reciple control
• PID loop control (future only)
• Ability to transfer recipes between Controller and PC computer.

********************************************************************
This was the quote from them:
V350-J-TR6 PLC+HMI+IO $970

V100-178-ET2 Ethernet card $178

EX-A2X IO Expansion Adaptor $92.05

IO-TO16 IO expansion module, 16 transistor out $224

Or

IO-RO16 IO expansion module, 16 Relay out. $276

Shipping $20.00
********************************************************************

Then added requirements: We need relay outputs to drive solenoid valves and contactors. 3 analog will be temperature and 3 analog will be 4-20mA.

And this was the follow up:
Alternative PLC:

V350-J-TR20 similar to the TR6 but only has 2 analogue inputs $825.00
Additional IO modules for direct temperature inputs.
IO-PT400 4x PT100 inputs $345
IO-ATC8 8x TC inputs (but also supports V and mA inputs via jumper configuration) $464


All units in stock in Sydney.
********************************************************************

 

[Inspire]

I had some Rockwell discussion, here's the cut/paste info below - hope it helps:
********************************************************
As discussed, Rockwell has low cost PLC Micro800. You can check the price starting from page 546 of the attached cataloque.The price is full listed price. I can ask whether they can give you 30% discount.

From Micro 820 model and up, it has Ethernet port built-in.

Please find the brochure for Micro 820 which we used in the past as the link below:
http://literature.rockwellautomation.com/idc/groups/literature/documents/pp/2080-pp004_-en-p.pdf


Free software can be download here
https://download.rockwellautomation...cv3i0cgwo636415762049654581&pageID=2052906914

Normally, we also use the HMI Touch Screen Panel connect to this PLC to display values, control setpoint and select recipe etc.

Personally, I prefer using Siemens product but they are expensive and the software is not free comparing with Rockwell product.

Basically, to find out what PLC you need, you need to know how many inputs and outputs are required for the job.

 

[BrunDog]

By no means is this a plug, so please understand my goal to add to the discussion...

Expensive and difficult-to-adopt PLCs for process automation were the impetus for us developing BruControl. We’ve always felt the manufacturer’s have a lot of leverage with their proprietary hardware, so using inexpensive microcontrollers, which work reliably and without OS’s, could serve as the I/O interfaces, including in a distributed manner.

There are some less expensive PLC options on the market such as the offerings from Automation Direct and other manufacturers. Siemens, Rockwell, ABB, Keyence, etc. have quality products but the costs are silly for our application and have a steep curve and/or require lots of time to program if you have no logic controller experience.

 

[augiedoggy]

can anyone tell me, are these actual plcs or just arduinos runing an os of some sort?
https://www.ebay.com/itm/Arduino-Et...453603?hash=item3f899920a3:g:pxcAAOSwH0JZ5QTL

https://www.ebay.com/itm/Arduino-In...432104?hash=item3f8998cca8:g:pxcAAOSwH0JZ5QTL

It would be cool if they can be easily setup to run brucontrol

 

[Inspire]

Arduino's are are basically open sourced PLC. You can do anything with Arduino. They will do what you program it to do. Those links are actual PLC, arduino open sourced PLC. It will run whatever you put into the SD card, and you can connect to that arduino through LAN cable.

I agree with BrunDog, PLC from a Company are old school. Expensive. Controlled. If you want to use PLC, go the open source route eg Arduino. More support, all open sourced, cheap parts, and you won't be controlled by a company. You can even go Raspberry Pi if you want an OS with GPIO pins to help do your automation.

 

[BrunDog]

@augiedoggy... yes, these should be able to run BC quite easily. They are MEGA based. The Ethernet should work out of the box. I don’t know about WiFi without more details of its chipset. The OLED display will not work out of the box but we can probably fix that. I may pick one up to test!

 

[Straykiller]

Anybody look into the Rockwell Micro 800 controllers?

Micro800 is a good basic plc series, the one downside is the software (connected components workbench) I have a lot of experience with rslogix 500 and rslogix 5000 so I’m not a fan. The software is free though so that’s a plus. The Micro820 runs about $260 and has built in Ethernet. I personally went with a micrologix 1100 becuse it has online editing and uses rslogix500. I am keeping my eye out for a compactlogix to use instead if it’s the right price. Just got two IFM Magnetic flow meters to add to my growing parts pile, should be a fun build once I acquire everything I need.