Is the Basic Stamp the right choice ?

Archiver

Greetings,

I am struggling whether the Basic Stamp (BS2P40 cause I need the I/O as
you'll see) is the right choice for my application. That is, in your opinion
would you recommend the Basic Stamp for the following application: Please
critique and comment on if the Basic Stamp will work for my application.

Because of the strong urging of my client I am designing 2 duplicate test
fixtures using the Basic Stamp to be used on the end of the client's mfg
lines to perform functionally test. Okay, here are the details.........

I will need to use a numeric keypad with a alphanumeric display. I am
planning on using example in Scott Edwards book, pg 195 for the keypad /
display. Also, I will need about 40 relays (250 VAC, 25 Amp) and 15
contactors (250 VAC, 25 Amp). For this I am considering an expanded version
of the circuit in the microcontroller application cookbook page 215. Each of
the individually addressable output lines will control a solid state relay
which in turn can energize a high power relay / contactor. Now comes the
crux of the matter, I need a method / instrument to take DC volt
measurements and AC volt measurements. I am considering the Fluke 45
multimeter controlled / communicating with either RS232 or RS485.

I know I am asking alot, but any help / comments you can provide are much
appreciated (in advance) !

To sum up, in my test fixture I need (A) a numeric keypad connected to a
alphanumeric display, (B) much I/O controlling high power relays and
contactors, and (C) a method / instrument capable of taking ACV and DCV
measurements and communicating (transmitting / receiving) the results to the
Basic Stamp.

What do you think ? I need to determine if I am barking up the wrong tree,
or if I should stay the course ???????????

Have a great 4th of July. Thank You !

Steve

Archiver

This sounds like you need to go with an Industrial type PLC.
Automation Direct (www.automationdirect.com) makes a very good one and it is
1/2 the price as Allen Bradley types. I have used them in the past in large
industrial projects that are too much for the Industrial Logic Controller I
build with Stamps. (The Stamp is still my first choice to use most of the
time.) I use them in welding and fabricating shops where the electrical noise
is very high.

You can get Keyboards, I/O, and A-D Converters to do all your measurements. I
like to use LCD Touch Screens as you can customize the Human Interface and
make it easier to use.

The downside is you have to learn Ladder Logic Programming and buy about an
extra $500 in programming software.

What you get in return is a Bulletproof Hardware System that is suited for
the factory floor. No reinventing the wheel needed.

Hope this helps,
Alan Bradford
Plasma Technologies

Archiver

I agree and disagree with Alan,

One question is what your software skills are ?

I am sure there are many people on the list who would considder the
industrial PLC route, just because they are not so well versed where
as others would not stop to ask the question, bucause they could go
from A to Z quickly.

If you are extreemly proficient and have already done all the
sfotware for interfaceing the LED, keypad, multiplexers... etc, then
you do not have a learing wall to climb.

if you can see that all this stuff could be done, you are correct,
but it will take time. and you will need to learn the programming,
then I would recomend you learn the 'Think and Do' software from
Automation direct. there you are basically just plugging in the
numbers. Much faster from when you start to when your customer
pushes that "ON" button.

I am not sure what your total in/output count is and if your customer
is anything like people I have delt with, add 50% to cover yourself.
in other words, if the 'best fit' system max's out at 24 points, and
you need 20, look long and hard at the next better system. Often it
is just a few dollars more to get twice the capability.

Dave




--- In basicstamps@y..., plasmastamp@a... wrote:
> This sounds like you need to go with an Industrial type PLC.
> Automation Direct (www.automationdirect.com) makes a very good one
and it is
> 1/2 the price as Allen Bradley types. I have used them in the past
in large
> industrial projects that are too much for the Industrial Logic
Controller I
> build with Stamps. (The Stamp is still my first choice to use most
of the
> time.) I use them in welding and fabricating shops where the
electrical noise
> is very high.
>
> You can get Keyboards, I/O, and A-D Converters to do all your
measurements. I
> like to use LCD Touch Screens as you can customize the Human
Interface and
> make it easier to use.
>
> The downside is you have to learn Ladder Logic Programming and buy
about an
> extra $500 in programming software.
>
> What you get in return is a Bulletproof Hardware System that is
suited for
> the factory floor. No reinventing the wheel needed.
>
> Hope this helps,
> Alan Bradford
> Plasma Technologies