PLC's Microcontrollers, doing it on the cheap

FYI

I Saw this post on microcontrollers, the problem is that you cannot
really get a PLC for a 100 bucks.

You have to buy all the components separately in most cases.

The Backplane- power supply

The CPU card

The Input or Output card each separate, and you will need both.

Also an ADC card to digitize the analog thermocouple voltage after
going through an amplifier.

Plus you need to buy the programming software which is 300-600
dollars.

Thus before you even get started you are now over a thousand dollars.

Due to this situation, I built a small 8 input and 8 output PLC
interface style controller which uses the BAsic Stamp from
www.parallaxinc.com an added plus is that their editor software for
programming is free.

This has been used in a variety of industrial applications to provide
control on the cheap.

The controller board is 289.00 and you can pick from about 4 flavors
of stamp microcontrollers from 49.00 to 75.00 dollars each, depending
on the amount of programming required to accomplish you task.

I downloaded the photos of this controller into the photo archives in
CAD_CAM_EDM_DRO. They are stored as bsiov2_2 and bsiov2_3

A second unit will be available shortly which will allow the
monitoring and control of 16 inputs and 16 outputs.

Both easily control and interface with ADC chips for analog voltages.

These ADC boards and specialty functions like DAC, PWM output and
Thermocouples are also in the works. If you have need of such, let
me know via e-mail. ronaldsa@...

Attached is more info on the controller:

*******************************************************************

For those working in the industrial environment, Digital Design
Solutions, Inc. annouces the release of a Programmable Industrial
Controller ala PLC Style which interfaces with 24 volt input and
output devices using the ever versatile Basic Stamp module.

All inputs are opto-isolated allowing for a good deal of
flexibility. The 8 Inputs are easily configured to use with both
flavors of industrial 24 volt sensors both PNP and NPN optical photo
sensors, or proximity sensors. The Inputs will also accept switches
or contacts, various photo transistors and hall effect sensors with
open collectors. Input Sensors derive their power from the 4
terminal input connections. Thus there is no need to assemble a large
section of DIN Rail terminal blocks to distribute power to Sensors.
A DIN Rail fuse block is recommended to power up this module.

TO-92 Darlingtons are used as open collectors on the 8 Outputs (500
ma capacity nominal for outputs) with flyback diodes on the board for
protection against inductive spikes when coupled with pneumatic
solenoids, relays or motors. Other features include a 5 volt
Switching Regulator: This results in high efficiency and low heat
when converting from 24 VDC to 5 volts with a 1.5 Amp Capacity @ 5
volts, should one wish to use a power hungry VFD Display with this
module. An LCD output connector is configured for a pin to pin mate
with a Serial LCD Backpack Interface.

This 8x8 Controller comes with DIN rail mountable plastic holder
ready for your application. Just add power, a BSII or BSIIe, your
sensors/outputs and some programming to have your industrial solution
up and running for a lot less money than an equivalent mini PLC.

The fully assembled controller with DIN rail mounting is available
for $289.00 For more information contact DDS via e-mail at:
ronaldsa@... or call 970-667-4239.

To purchase send check or money order to:

Digital Design Solutions, Inc.
1937 Hyde Drive
Loveland, CO. 80538

VISA is accepted via www.paypal.com

********************************************************************

>
> Message: 15
> Date: Sat, 10 Feb 2001 22:09:12 -0000
> From: davemucha@...
> Subject: Re: cast iron
>
> (sorry if is this is a second post, Yahoo and I don't get along, it
> sends stuff when I hit the tab key)
>
> For a controller, you can get a PLC from
> www.automationdirect.com for about $100. It'll allow you to

program

> any type of ramp up and down and hold cycles you can imagine.
> A thermocouple will allow you to monitor the temperature and if you
> want, a second will allow you to monitor the part in the oven.
>
> or if you want, you can visit http://www.parallaxinc.com/ and get

a

> micro-controller and create you own device. Free software and a
> GREAT list at basicstamps on yahoo
> http://www.egroups.com/messagesearch/basicstamps?query
>
>
>
>
> --- In CAD_CAM_EDM_DRO@y..., "Smoke" <gordonr@r...> wrote:
> > Jay, do you know of a source for programable controllers and high
> > temperature heating elements we could incorporate into home built
> electric
> > heating/melting furnaces?
> >
> > I'd love to build a somewhat larger heat treating furnance and I
> know of
> > others who'd like to do this as well. In fact, I just got a post

at

> > HomeFoundry about a guy that wants to build an elcectric furnace

for

> > controlling temperatures on salt baths.
> >
> > Smoke
> >