What PLC is best for me please

Hello

Im looking for a PLC with these specs, any ideas of what i need?

1000 program steps

digital inputs 15 x 24 volts opto isolated

digital outputs 7 x (24v relay with 1 A rated contacts)

analogue inputs of 3 x (maximum i/p + 10 V)

analogue outputs of 1 x (maximum o/p + 10 V)

Im really really stcuk so any help is great

Thanks in advance

Lennie.

Hey Lennie,

Pretty much most PLC makes will have a type for your specs given, but the main question should be, have you a plant norm, ? do you have software ? what type of industry etcetc, the specs you gave only tell us a small part of the full question ? so do you have any kmake preference ?

maybe this?

check this out: --> http://web2.automationdirect.com/adc/Shopping/Catalog/PLC_Hardware/DirectLogic_205

The more flexible makes of PLC's I've worked with are Allen bradley the SLC 503 with its various cards will suit your needs. Omron or Automation direct are also flexible enough to handle what you are doing. as mentioned before most times it will depend on which PLC's your plant is best setup to handle.

Any reputable PLC supplier can meet those requirements, and although there will be price differences they shouldn't be the basis of your decision. If you are a PLC rookie I suggest you contact a couple of suppliers and ask for there recommendation. Find out what kind of technical support they are willing to offer. Find out if they offer training should you need it. Find out what kind of inventroy they have. Find out if there are any major users in your area.

My favorite PLC is AutomationDirect.com, but I hesitate to recommend them for someones first ever automation project because you can't get hands on support. I would avoid Siemens because they are incredibly difficult to work with. Other than that, most of the majors would be a reasonable choice.

Tom Jenkins said:

My favorite PLC is AutomationDirect.com, but I hesitate to recommend them for someones first ever automation project because you can't get hands on support.

Click to expand...

AD is where I learned, not to mention the only PLC I've used. I found that by working through the basic examples in the manual I was able to pick up 90% of what I needed in a couple of days. Their tech support, while not local, is really good at working with the newbies.

Lennie,

Your requirements are by no means out of the realm of the majority of PLC manufacturers. That being said, you will want to base your decision on the following:

1. Does the manufacturer have a product that meets my needs?

2. Is the price of their solution reasonable for my budget?

3. How good is the support? What level of support do they provide? How accessible are they when you have questions?

4. What additional costs are there? (software, support, manuals, cables)

Remember, not all manufacturers are created equal. Tom gave you a couple of examples, including one that he works with all the time.

Speaking as a manufacturer, we try to offer our customers as much hands on support as possible. No voice mail during regular hours. Direct access with technical support.

Have you looked at any manufacturers yet? If so, who and what have they told you?

Disclosure: I am a representative for Entertron Industries, manufacturer of embedded programmable logic controllers.

Hope this helps.

God Bless,

marksji said:

AD is where I learned, not to mention the only PLC I've used. I found that by working through the basic examples in the manual I was able to pick up 90% of what I needed in a couple of days. Their tech support, while not local, is really good at working with the newbies.

Click to expand...

It is a tough call, Mark. I hadn't used too many other brands before I started with ADC, and I agree their support and examples, combined with their excellent documentation, made picking up their system very easy. On the other hand, I had experience with relay based logic, serial communications, and analog controllers, so I knew the fundamentals fairly well.

If this is Lennie's first automation project he might want local support. There is nothing worse than not getting an input to turn on, and not knowing if it is wiring, the field device, software, a comm cable, or ........ A two minute actual viewing and hands-on help from a local tech support engineer can resolve an issue that might otherwise take hours and hours to figure out.

On the other hand, if he feels comfortable with the other aspects of an automation system and this is just his first PLC project, then ADC is as good as it gets.

Tom Jenkins said:

I had experience with relay based logic, serial communications, and analog controllers, so I knew the fundamentals fairly well.

If this is Lennie's first automation project he might want local support. There is nothing worse than not getting an input to turn on, and not knowing if it is wiring, the field device, software, a comm cable, or ........

Click to expand...

Good point Tom, I hadn't really thought of that... Guess I take my own background a bit for granted. I started working with PLC's and automation all at the same time, but I was a 2 years into my EE degree when I started working part time for the company I still work for so the electrical part wasn't difficult for me.

PLC: http://www.automationdirect.com/adc/Shopping/Catalog/PLC_Hardware/DirectLogic_06/PLC_Units/D0-06DR

Analog input/output: http://web2.automationdirect.com/ad...are/DirectLogic_06/Option_Modules/F0-4AD2DA-2

Software: http://web2.automationdirect.com/ad...gic_06/Programming_SW_-a-_Cables/PC-PGM-BRICK

Cable: http://web2.automationdirect.com/ad...ng_-a-_Communication_Cables_for_PLCs/D2-DSCBL

This meets your specs, and about $700.00 will get you going.

You also might want to check with Enteron. I've always wanted to check them out, but dont have the time right now.

Stephen didnt put in the link to Entertron so I am posting one to a model that will easily match your requriemensts:
http://www.entertron.com/sk1600ric.htm

Stephen also didnt mention they offer their programming software free. That can be obtained here: http://www.entertron.com/software.htm

I am not sure about Siemens being left out, the S7-200 isnt that hard to learn and/or deal with. They also sell a training package that is reasonable.
http://www2.automation.siemens.com/s7-200/html_76/uebersicht.htm

Siemens also offers free online basic training courses for PLCs and more:
http://www.sea.siemens.com/step/default.html

Other common brands that may be easy to obtain and get support for locally would be Allen Bradley, Mitsubishi, Omron and GE.

You have been given links to a couple of plc's, that I would recommend. With your I/O requirements, and combination of analog and digital, I would recommend going with Entertron (link on RSDoran post), as you will receive everything in one piece, not having to plug and play, then configure (or attempt to configure). You will get good phone tech support from both AD and Entertron.

I have programmed both, and lean more towards Entertron as being a little easier on me. I like Entertron's simulator part of the program, that allows you to write your program and test it, with out having to have the plc connected to the computer. Plus the software is FREE.

I find GE Fanuc to be the easiest to program (years of practice), but am not going to recommend them, as they are not the best suited for your application, speccially if your budget is not big. I also am not recommending Moeller's easy relays, which could do the job, but it sounds like you do not have extensive plc experience. Allen Bradley are probably beyond your budget and experience. I will use them, when someone else foots the bill.

best regards.....casey

I'm not totally clear on the Enteron's Analog setup. Is it a seperate interface device or on board?

kc9ih said:

Allen Bradley are probably beyond your budget and experience. I will use them, when someone else foots the bill.

best regards.....casey

Click to expand...

I won't even do that if someone wants to pay for it. It costs too much in development time to completely change over one of our machines just for a one-up.

My thoughts

Started out with IDEC then SQD then AD then AB with a little AD. In my opinion Allen Bradley is easier than AD to develope a program. When I say AB I`m talking Slicks and Micros don`t know the new logixs and don`t care to learn. I like AB because it makes the math easier and the subs are not after the END of the program. I`m not saying you can do anything with AB you can`t do with AD. With AB you can just easierly see what you`ve got when you get through. Seems less complicated. And when it comes to net working it`s all there. Now I will say this as for as support we probably have better support (because of at least three people I can think of) on this :site: than what we pay for. Now this is just my opinion and like A you know what everybody has one. You would have a hard time convincing me AB doesn`t on AD or vise versa.