What PLC is good for a beginner?

[DennisCNC]

I got a project that will need a some simple operations to be controlled by a PLC, what brand or model should I start with? I have not programmed any PLC's before, but I did some BasicStamp programming.

It will need about 5-9 inputs and 5-9 outputs.

I have looked and looked there is so many options


Thanks

[Al_The_Man]

Automation Direct seems popular among new PLC users, although I have not used it.
Although many of the main PLC's can be picked up on ebay really cheap, the cost is in the software, unless you can also get a seller to supply a copy.
I personally prefer either Mitsubishi or Allen-Bradley.
Idec & Omron are a couple more to chose from.
They all have very similar characteristics, it depends on the level of complexity you require in the function set.
Most of them offer the I/O choice difference in AC/DC In, AC/DC out, solid state/relay etc.
Another option that does not require software for very simple functions is a Smart Relay, Most of these sold by different companies are made by the same manufacturer.
The are virtually a very simple PLC, but very limited in instructions, basic boolean logic.
Al.

[niclatrique]

FP0 from matsushi_ta Electronic Works or, MEW --> the Panasonic industrial line try www.aromat.com

ELC from Cutler Hammer are great too. They are small, cheap, expandable and has a great instruction set.

EASY from Klockner Moeller or LOGO from Siemens are programmable relays. the LOGOs are expandable and cheap. No software needed no cable needed too. Could a great choice.

In the case of any other you would have to buy a software licence and a programming cable.

good luck

nic

[NinerSevenTango]

Check out www.ezautomation.net.

Whatever you use, you will have to borrow or buy software to program it with. (Don't forget the cost of the cable!) The EZ plc is probably the lowest total cost out there. The programming interface is very easy to learn, and the price for it is not outlandish like so many others. I've built several pretty complicated machines using several of their models, and have had good luck with them. Very sophisticated control capability for a very low price. I even wrote a program to communicate with them over ethernet. I've got one machine running automatically with 16 inputs, 16 outputs, analog ins and outs, high speed counter card, using a touch screen interface, and doing datalogging to an office pc over the network, for about the price of one Allen Bradley network card.

After using several brands, being an early adopter on the automationdirect stuff (hope you like working in octal and hex), even doing motion control with the low end units, I've settled pretty much exclusively on the EZ plc's.

PM me if you need help. I do this crap for the fun of it, mostly.

--97T--

[DennisCNC]

Thanks for the input ALL!!! More Q's to come

[epineh]

Could you keep with a micro? If you used the Basic Stamp have you checked out Parallax's new chip, the Propeller chip? It's fast, cheap, got heaps of features, and I'm sure with a few H-bridges would probably leave most cheap PLC's for dead. Runs at 80 MHz, has 8 seperate processors for multi-tasking yadda yadda...

I'm not afilliated in any way, just got one and am pretty impressed. The documentation and support for noobies (like me) is terrific. Soon as Christmas is finished, intend to get to work on a stepper driver with quadrature feedback and correction.

Worth a look any way.

Russell.

[DennisCNC]

After looking around more at PLC's I think it will be more economical to go the microcontroller route. I have PicBasic but never wrote any programms with it, got busy with other projects. I'm thinking of buying this board:http://circuit-ed.com/easypic4.htm
PLC's started to intimidate me with all the different options and software and cables that you need.

[djvoigt]

Originally Posted by DennisCNC I got a project that will need a some simple operations to be controlled by a PLC, what brand or model should I start with? I have not programmed any PLC's before, but I did some BasicStamp programming. It will need about 5-9 inputs and 5-9 outputs. I have looked and looked there is so many options Thanks

HAVE YOU TRIED ALLEN-BRADLEY?

[rcrabb]

Allen Bradley would be your best bet. But the cost of software would break the bank.

Automation Direct Plc's are very nice units for the price and the software is reasonably priced. The same goes for EZplc.

The micro controller would be the the most inexpensive hardware but the most work programing and circiut building.

If your time is worth money go for the automation direct Plcs. Good price. Easy software.

[Rhodan]

There's an in-betweener gizmo you might be interested in called the CUBLOC. Its an Atmel AVR chip with PLC components added around it. The software is free and the programming cable is a plain old serial cable. Best of all, its dirt cheap compared to PLCs and actually quite cheap even for micros.

Programming is done in both/either Basic or Ladder Logic (ladder works like an RTOS, Basic comes after ladder if ladder is used).

Products range from a small stampish sized CB220 up to the CUTouch. all have external interrupts, RS232, ADCs, PWM, I2C and various other whizbang features.

I have the CUTouch, damned nice unit! 5.7" touchscreen (B&W) with two Atmel ATMega 128s - one does the touchscreen and the other runs programs. Scads of IO (Transistor outputs and optically isolated inputs, PWM, External interrupts, ADC, the whole shebang).

You can mix and match different parts - add a graphic LCD or 7 segment display, toss in various "I/O Cells" - pre-built input and output options that are dirt cheap and plug into a nice pre-built board. One of the models even has a socket for plugging in an XPort (webserver/serial-to-ethernet module).

Take a gander over at http://cubloc.com/index.php. Prices are right on the website, so no guessing required.

[xlukkajr]

if you are interested a have a very good condition OMRON plc complete with all IO and psu It is in very good condition i can send you some photos of it if you are interested contact me On : gcharles@maltanet.net

[rcrabb]

First time I've seen CUBLOC. Looks like a perfect fit for Dennis.