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Subject: Stagecraft Digest #50
Date: Thu, 24 Jun 2004 03:00:38 -0700
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For info, archives & UNSUBSCRIBE, see <http://stagecraft.theprices.net/>
---------------------------------------------------

Stagecraft Digest, Issue #50

 1. Re: Powerful
    by Bsapsis [at] aol.com
 2. Re: Powerful
    by "Dr. Randall W.A. Davidson" <doomster [at] worldnet.att.net>
 3. Re: Powerful
    by "Dr. Randall W.A. Davidson" <doomster [at] worldnet.att.net>
 4. Re: need letter
    by "Paul Guncheon" <paul.guncheon [at] verizon.net>
 5. Re: need letter
    by "Tony Deeming" <deeming.tony [at] btinternet.com>
 6. Re: Powerful
    by "Rob Carovillano" <rcarovil [at] sju.edu>
 7. Re: Powerful
    by usctd [at] columbia.sc
 8. Re: Powerful
    by Bsapsis [at] aol.com
 9. Re: Weighty Subject
    by CB <psyd [at] cox.net>
10. Re: Weighty Subject
    by Jerry Durand <jdurand [at] interstellar.com>
11. Re: Weighty Subject
    by "Tony Deeming" <deeming.tony [at] btinternet.com>
12. Looking for a good home...
    by "Fred Schoening, Jr." <bigfred [at] mindspring.com>
13. Re: Looking for a good home...
    by "Fred Schoening, Jr." <bigfred [at] mindspring.com>
14. Cheap D/A circuitry
    by "Ben Kehoe" <bkehoe01 [at] hamline.edu>
15. Re: Cheap D/A circuitry
    by "MARK OBRIEN" <omark4 [at] msn.com>
16. Re: Cheap D/A circuitry
    by "MARK OBRIEN" <omark4 [at] msn.com>
17. Re: Cheap D/A circuitry
    by Jerry Durand <jdurand [at] interstellar.com>
18. Re: Cheap D/A circuitry
    by "Brian Busch" <bpbusch [at] techie.com>

*** Please update the subject line of your reply to use the subject
*** line of the message you are replying to! Please only reply to
*** one message subject in each reply.

----------------------------------------------------------------------

From: Bsapsis [at] aol.com
Message-ID: <1dd.24bd111a.2e0ab135 [at] aol.com>
Date: Wed, 23 Jun 2004 06:11:01 EDT
Subject: Re: Powerful


In a message dated 6/23/04 5:44:39 AM, gwilliams [at] appstate.edu writes:

<< And for those who don't know it, more congrats are in order. Sapsis 
Rigging teamed with Flying By Foy to fly the Olympic Torch into Times 
Square this past weekend. I've seen the replays, and it was fan-tast-ic. >>

Aw shucks.  tweren't nuthin'.  (head down.  Embarrassed pose. Blushing)

Sapsis Rigging, Inc.
www.sapsis-rigging.com
800.727.7471
800.292.3851 fax
267.278.4561 mobile
We stand behind, and under, our work.
                             


------------------------------

From: "Dr. Randall W.A. Davidson" <doomster [at] worldnet.att.net>
Subject: Re: Powerful
Date: Wed, 23 Jun 2004 03:19:40 -0700
Message-ID: <004e01c4590b$993b5010$726dfea9 [at] DrDoomsComputer>
In-Reply-To: <list-3713171 [at] prxy.net>

Hmn. Twernt nothing. Well, maybe, William, maybe. You do all right.
doomster

====================================================
THE FIRST NATIONAL CONGRESS ON HEALTH AND SAFETY FOR THE PERFORMING ARTS
IN THE SECONDARY SCHOOLS  -  Sponsored by ISETSA
June 25, 26, 27, 2004 at Cardinal Stritch University, Milwaukee,
Wisconsin
====================================================
Risk International & Associates, Inc.  -  Dedicated to making the world
a healthier & safer place.
Website: www.riskit.com E-mail: rdavidson [at] riskit.com
====================================================
International Secondary Education Theater Safety Association (ISETSA)  -
Dedicated to the protection of every student in the performing arts.
Website: www.isetsa.org E-mail: info [at] isetsa.org
====================================================
960 E. Bonita #158, Pomona, CA 91767    Phone/Fax: (909) 625-5961
====================================================

-----Original Message-----
From: Stagecraft [mailto:stagecraft [at] theatrical.net] On Behalf Of
Bsapsis [at] aol.com
Sent: Wednesday, June 23, 2004 3:11 AM
To: Stagecraft
Subject: Re: Powerful

For info, archives & UNSUBSCRIBE, see <http://stagecraft.theprices.net/>
---------------------------------------------------


In a message dated 6/23/04 5:44:39 AM, gwilliams [at] appstate.edu writes:

<< And for those who don't know it, more congrats are in order. Sapsis 
Rigging teamed with Flying By Foy to fly the Olympic Torch into Times 
Square this past weekend. I've seen the replays, and it was fan-tast-ic.
>>

Aw shucks.  tweren't nuthin'.  (head down.  Embarrassed pose. Blushing)

Sapsis Rigging, Inc.
www.sapsis-rigging.com
800.727.7471
800.292.3851 fax
267.278.4561 mobile
We stand behind, and under, our work.
                             


------------------------------

From: "Dr. Randall W.A. Davidson" <doomster [at] worldnet.att.net>
Subject: Re: Powerful
Date: Wed, 23 Jun 2004 03:20:56 -0700
Message-ID: <004f01c4590b$c6134340$726dfea9 [at] DrDoomsComputer>
In-Reply-To: <list-3713016 [at] prxy.net>

50 most powerful people. Wow. Maybe someday I could, nah, just a
thought. Congrats on all that power and recognition. Doomster.

====================================================
THE FIRST NATIONAL CONGRESS ON HEALTH AND SAFETY FOR THE PERFORMING ARTS
IN THE SECONDARY SCHOOLS  -  Sponsored by ISETSA
June 25, 26, 27, 2004 at Cardinal Stritch University, Milwaukee,
Wisconsin
====================================================
Risk International & Associates, Inc.  -  Dedicated to making the world
a healthier & safer place.
Website: www.riskit.com E-mail: rdavidson [at] riskit.com
====================================================
International Secondary Education Theater Safety Association (ISETSA)  -
Dedicated to the protection of every student in the performing arts.
Website: www.isetsa.org E-mail: info [at] isetsa.org
====================================================
960 E. Bonita #158, Pomona, CA 91767    Phone/Fax: (909) 625-5961
====================================================

-----Original Message-----
From: Stagecraft [mailto:stagecraft [at] theatrical.net] On Behalf Of Greg
Williams
Sent: Wednesday, June 23, 2004 2:45 AM
To: Stagecraft
Subject: Re: Powerful

For info, archives & UNSUBSCRIBE, see <http://stagecraft.theprices.net/>
---------------------------------------------------


On Tuesday, June 22, 2004, at 04:00  PM, Rob Carovillano wrote:

> Congrats to Bill on being named to the 50 most powerful people in
> Entertainment Technology list.

Congratulations, Bill!

And for those who don't know it, more congrats are in order. Sapsis 
Rigging teamed with Flying By Foy to fly the Olympic Torch into Times 
Square this past weekend. I've seen the replays, and it was fan-tast-ic.

Altogether, everyone, on 3. 1... 2... 3... "Yeeeee-haw"! (insert loud 
congratulatory noise appropriate to your area here).

-=Greg Williams=-
Production Manager
Valborg Theatre
Appalachian State University


------------------------------

Message-ID: <000501c45928$f7eec200$0202a8c0 [at] MyLastPC>
From: "Paul Guncheon" <paul.guncheon [at] verizon.net>
References: <list-3713125 [at] prxy.net>
Subject: Re: need letter
Date: Wed, 23 Jun 2004 03:49:55 -1000

<<I think Kate ran out of vowels.  I guess o's are the first to go.  Here
are a few vowels for Kate:  ooooooeeeeeeeeeeuuuuuuuuuuuuiiiiaaaaaa>>

Anybody got any "eth-th"?

Later,

Paul

"Emily put on weight," thaid Tom emphatically. 




------------------------------

Message-ID: <011101c45929$6cc7a150$0a01a8c0 [at] Tony>
From: "Tony Deeming" <deeming.tony [at] btinternet.com>
References: <list-3713125 [at] prxy.net> <list-3714284 [at] prxy.net>
Subject: Re: need letter
Date: Wed, 23 Jun 2004 14:53:12 +0100


----- Original Message ----- 
From: "Paul Guncheon" <paul.guncheon [at] verizon.net>
To: "Stagecraft" <stagecraft [at] theatrical.net>
Sent: Wednesday, June 23, 2004 2:49 PM
Subject: Re: need letter


> For info, archives & UNSUBSCRIBE, see <http://stagecraft.theprices.net/>
> ---------------------------------------------------
> 
> <<I think Kate ran out of vowels.  I guess o's are the first to go.  Here
> are a few vowels for Kate:  ooooooeeeeeeeeeeuuuuuuuuuuuuiiiiaaaaaa>>
> 
> Anybody got any "eth-th"?
> 

Or exth'th?

9 - V F N 10 E X.....!


------------------------------

Message-ID: <002901c45932$e371cf20$a8a44481 [at] rcarovil>
From: "Rob Carovillano" <rcarovil [at] sju.edu>
References: <list-3713125 [at] prxy.net>
Subject: Re: Powerful
Date: Wed, 23 Jun 2004 11:00:55 -0400

Bill, et al,

I only get the digest, so in case no one has answered yet... The list was in
the new July issue of Entertainment Design.  There is also a blurb about the
ride to Long Beach too.  Surprised that they didn't contact you.  There is
even a picture.  Your welcome to stop by here anytime you want.  We are
pretty dead for the next two months.  We had some additional counterweight
linesets installed last summer and I would love to complain to you about the
company that did the installation.  Supposedly they gave them a maintenance
contract too, which is unfortunate because there is a lot of maintenance
that needs to be done and I don't think it will.  Unfortunately it was one
of those times when no one bothered informing me of anything to do with the
project.  I think I have that problem rectified.

Rob Carovillano
Technical Director
Bluett Theatre
Saint Joseph's University
610-660-1044
rcarovil [at] sju.edu


------------------------------

Message-ID: <1492.207.201.197.55.1088006036.squirrel [at] webmail.columbia.sc>
In-Reply-To: <list-3713016 [at] prxy.net>
References: <list-3707612 [at] prxy.net> <list-3713016 [at] prxy.net>
Date: Wed, 23 Jun 2004 11:53:56 -0400 (EDT)
Subject: Re: Powerful
From: usctd [at] columbia.sc

Congrats, Bill.

Is there a video of the torch thing on-line?  I did not get to see it.
-- 
Eric Rouse
TD-University of SC, Columbia
Freelance Foyboy

> For info, archives & UNSUBSCRIBE, see <http://stagecraft.theprices.net/>
> ---------------------------------------------------
>
>
> On Tuesday, June 22, 2004, at 04:00  PM, Rob Carovillano wrote:
>
>> Congrats to Bill on being named to the 50 most powerful people in
>> Entertainment Technology list.
>
> Congratulations, Bill!
>
> And for those who don't know it, more congrats are in order. Sapsis
> Rigging teamed with Flying By Foy to fly the Olympic Torch into Times
> Square this past weekend. I've seen the replays, and it was fan-tast-ic.
>
> Altogether, everyone, on 3. 1... 2... 3... "Yeeeee-haw"! (insert loud
> congratulatory noise appropriate to your area here).
>
> -=Greg Williams=-
> Production Manager
> Valborg Theatre
> Appalachian State University
>
>


------------------------------

From: Bsapsis [at] aol.com
Message-ID: <79.2cd10bdd.2e0afe6b [at] aol.com>
Date: Wed, 23 Jun 2004 11:40:27 EDT
Subject: Re: Powerful


In a message dated 6/23/04 11:10:18 AM, usctd [at] columbia.sc writes:

<<


Is there a video of the torch thing on-line?  I did not get to see it. >>

I'm told that the entire Torch Lighting ceremony, mind numbing speeches and 
all, is on-line at NYC.gov.  The Torch across Times Square is at the end.  
There should be a link toward the bottom of the page.  I've tried to access the 
page with no success so far.


Be well
Bill

Sapsis Rigging, Inc.
www.sapsis-rigging.com
800.727.7471
800.292.3851 fax
267.278.4561 mobile
We stand behind, and under, our work.
                             


------------------------------

Message-Id: <3.0.6.32.20040623082049.01829d00 [at] pop.west.cox.net>
Date: Wed, 23 Jun 2004 08:20:49
From: CB <psyd [at] cox.net>
Subject: Re: Weighty Subject

>On the assumption that you're NOT taking this seriously as a wind-up, I'm
>going to leave it alone now.....!

Good call!  I was only a bit serious.  Not that I'd ever suggest that fire
doors be propped open (other than temporarily, to move, say, a big set
through or loading the FOH gear through), if the idiots are going to prop
open a fire door, using a fire extinguisher seemed the comedic- and
ironicly appropriate prop.

------------------------------

Message-Id: <6.1.1.1.0.20040623090928.0c37caa8 [at] localhost>
Date: Wed, 23 Jun 2004 09:13:20 -0700
From: Jerry Durand <jdurand [at] interstellar.com>
Subject: Re: Weighty Subject
In-Reply-To: <list-3715132 [at] prxy.net>
References: <list-3715132 [at] prxy.net>

At 01:20 AM 6/23/2004, you wrote:
>Good call!  I was only a bit serious.  Not that I'd ever suggest that fire
>doors be propped open (other than temporarily, to move, say, a big set
>through or loading the FOH gear through), if the idiots are going to prop
>open a fire door, using a fire extinguisher seemed the comedic- and
>ironicly appropriate prop.

When I worked in semiconductors, I had a lot of trouble getting the workers 
in my lab to NOT store the chemicals in the emergency shower.  (say with a 
whine) "But, the chemical storage cabinets are in the hall outside the lab 
and this is right here."  Often I'd find a stack of bottles of acids, 
solvents, etc. wedged wall to wall in the shower.  I guess the people who 
worked for me never took showers.  :(



----------
Jerry Durand
Durand Interstellar, Inc.
219 Oak Wood Way
Los Gatos, California 95032-2523  USA
tel:  +1 408 356-3886
fax:  +1 408 356-4659
web:  www.interstellar.com



------------------------------

Message-ID: <021801c45943$9fae07c0$0a01a8c0 [at] Tony>
From: "Tony Deeming" <deeming.tony [at] btinternet.com>
References: <list-3715132 [at] prxy.net>
Subject: Re: Weighty Subject
Date: Wed, 23 Jun 2004 17:52:16 +0100


----- Original Message ----- 
From: "CB" <psyd [at] cox.net>
To: "Stagecraft" <stagecraft [at] theatrical.net>
Sent: Wednesday, June 23, 2004 8:20 AM
Subject: Re: Weighty Subject


> For info, archives & UNSUBSCRIBE, see <http://stagecraft.theprices.net/>
> ---------------------------------------------------
>
> >On the assumption that you're NOT taking this seriously as a wind-up, I'm
> >going to leave it alone now.....!
>
> Good call!  I was only a bit serious.  Not that I'd ever suggest that fire
> doors be propped open (other than temporarily, to move, say, a big set
> through or loading the FOH gear through), if the idiots are going to prop
> open a fire door, using a fire extinguisher seemed the comedic- and
> ironicly appropriate prop.
>

8-)))))

Ynot



------------------------------

Message-ID: <850134.1088015113383.JavaMail.root [at] wamui07.slb.atl.earthlink.net>
Date: Wed, 23 Jun 2004 13:25:13 -0500 (GMT-05:00)
From: "Fred Schoening, Jr." <bigfred [at] mindspring.com>
Subject: Looking for a good home...

...for our lovely and talented Production Administrator, who is being downsized out of a job. I know we don't ordinarily post "looking for a job" type messages here, but I'm hoping y'all won't mind just this once. Her name is Alicia Prado, and "they" have decided to reduce her position to an internship for this coming season. Alicia is very bright, personable, responsible, smart, thorough, and many other good things that make her a very enjoyable person to work with. We're going to miss her sorely.

Unfortunately, she's having a bit of trouble finding any suitable openings, so I thought I'd see if any of you might be looking for Top Quality Personnel such as Alicia.

If you're interested, here's her contact info:

Alicia Prado
Production Administrator
2401 Flora St
Dallas, TX 75201

voice: 214 922 0422 x22
fax: 214 922 0430
Alicia.Prado [at] DallasTheaterCenter.org

She'll be here until the end of the month. After that, I can relay any messages to her or get you some updated contact info. Also, feel free to contact me or the Production Manager, Charley Rickett (same number, x11), for more details.

Thanks for the bandwidth,

Fred



"Big Fred" Schoening
Assistant Technical Director
Alliance Theatre Company

Fred.Schoening [at] WoodruffCenter.org
phone: 404 351-4754
fax: 404 351-8298

"... a root word of technology, techne, originally meant 'art.' The ancient Greeks never separated art from manufacture in their minds, and so never developed separate words for them."
-- Robert M. Pirsig, Zen and the Art of Motorcycle Maintenance

------------------------------

Message-ID: <8693801.1088015487709.JavaMail.root [at] wamui07.slb.atl.earthlink.net>
Date: Wed, 23 Jun 2004 13:31:27 -0500 (GMT-05:00)
From: "Fred Schoening, Jr." <bigfred [at] mindspring.com>
Subject: Re: Looking for a good home...

Uh, oops - please ignore the outdated sig on my last post. It should be:

"Big Fred" Schoening
Technical Director
Dallas Theater Center
Dallas, Texas, USA

214 922 0422 x12
fax: 214 922 0430

original message:


------------------------------

Subject: Cheap D/A circuitry
From: "Ben Kehoe" <bkehoe01 [at] hamline.edu>
Date: Wed, 23 Jun 2004 13:34:55 -0500
Message-ID: <1088015695.94388960bkehoe01 [at] hamline.edu>

I am building a basic motion platform, a 4x8 wagon powered by two 3/4 hp mo=
tors.  I'm using a PLC from automationdirect, the basic 05 model, to cont=
rol the motors.  The speed controls I'm using have a 0-10v control circui=
t, and I want to connect the PLC to this.  I could buy the analog-out opt=
ion module, but I was wondering if anyone knew how I could go about buyin=
g or making a digital to analog converter that would take a signal from t=
he high-speed outputs on the PLC and use it to regulate a current to the =
speed control.  The resolution wouldn't have to be more than 8 bit, it's =
not a precision operation.  Thanks.
 
Ben Kehoe



------------------------------

From: "MARK OBRIEN" <omark4 [at] msn.com>
Subject: Re: Cheap D/A circuitry
Date: Wed, 23 Jun 2004 14:14:19 -0700
Message-ID: <BAY3-F19m4iZrbUMjA200004699 [at] hotmail.com>

Greetings,

In looking at this, I saw a few things to wonder about.

>I am building a basic motion platform, a 4x8 wagon powered by two 3/4 hp 
>motors.

Is this one platform, two motors?  How does that work out?  Are said motors 
connected, and have to have the EXACT speed?

I have tried to do a similar thing, and even though I had two motor controls 
following the same signal, the results were less than perfect.  What 
benefits do you get from two motors?


>I'm using a PLC from automationdirect, the basic 05 model, to control the 
>motors.

What software are you using?


>  The speed controls I'm using have a 0-10v control circuit, and I want to 
>connect the PLC to this.

Is this 0-10v, plus direction,  or -10 to +10v bipolar signal?

>I could buy the analog-out option module, but I was wondering if anyone 
>knew how I could go about buying or making a digital to analog converter 
>that would take a signal from the high-speed outputs on the PLC and use it 
>to regulate a current to the speed control.  The resolution wouldn't have 
>to be more than 8 bit, it's not a precision operation.

Part of the logic of buying a PLC "system" as per se.  Is to have everything 
play well with others.  Introducing some other piece of hardware into the 
mix will sometimes work, and sometimes will not.  I have found the less 
variables involved, the better.  Furthermore, sometimes it will work fine 
sometimes, but not at others.  A BIG problem in having your controller 
follow a signal, is that any noise that gets into the system could cause 
inaccurate speed at best, and unexpected movement, at worst.  Runaway motors 
can be NASTY.

Usually, PLC components have a opto isolation setup built into the circuit, 
because different components could have a different potential to ground at 
any given moment. BAD.

My opinion would be to use the components made for what you are doing, and 
just spend the extra buck.


Mark O'Brien


>
>Ben Kehoe
>
>

_________________________________________________________________
From ‘will you?’ to ‘I do,’ MSN Life Events is your resource for Getting 
Married. http://lifeevents.msn.com/category.aspx?cid=married


------------------------------

From: "MARK OBRIEN" <omark4 [at] msn.com>
Subject: Re: Cheap D/A circuitry
Date: Wed, 23 Jun 2004 14:11:08 -0700
Message-ID: <BAY3-F128z2etaV4i2C00004416 [at] hotmail.com>

Greetings,

In looking at this, I saw a few things to wonder about.

>I am building a basic motion platform, a 4x8 wagon powered by two 3/4 hp 
>motors.

Is this one platform, two motors?  How does that work out?  Are said motors 
connected, and have to have the EXACT speed?

I have tried to do a similar thing, and even though I had two motor controls 
following the same signal, the results were less than perfect.  What 
benefits do you get from two motors?


>I'm using a PLC from automationdirect, the basic 05 model, to control the 
>motors.

What software are you using?


>  The speed controls I'm using have a 0-10v control circuit, and I want to 
>connect the PLC to this.

Is this 0-10v, plus direction,  or -10 to +10v bipolar signal?

>I could buy the analog-out option module, but I was wondering if anyone 
>knew how I could go about buying or making a digital to analog converter 
>that would take a signal from the high-speed outputs on the PLC and use it 
>to regulate a current to the speed control.  The resolution wouldn't have 
>to be more than 8 bit, it's not a precision operation.

Part of the logic of buying a PLC "system" as per se.  Is to have everything 
play well with others.  Introducing some other piece of hardware into the 
mix will sometimes work, and sometimes will not.  I have found the less 
variables involved, the better.  Furthermore, sometimes it will work fine 
sometimes, but not at others.  A BIG problem in having your controller 
follow a signal, is that any noise that gets into the system could cause 
inaccurate speed at best, and unexpected movement, at worst.  Runaway motors 
can be NASTY.

Usually, PLC components have a opto isolation setup built into the circuit, 
because different components could have a different potential to ground at 
any given moment. BAD.

My opinion would be to use the components made for what you are doing, and 
just spend the extra buck.


Mark O'Brien


>
>Ben Kehoe
>
>

_________________________________________________________________
FREE pop-up blocking with the new MSN Toolbar – get it now! 
http://toolbar.msn.click-url.com/go/onm00200415ave/direct/01/


------------------------------

Message-Id: <6.1.1.1.0.20040623154635.02790380 [at] localhost>
Date: Wed, 23 Jun 2004 15:48:59 -0700
From: Jerry Durand <jdurand [at] interstellar.com>
Subject: Re: Cheap D/A circuitry
In-Reply-To: <list-3716481 [at] prxy.net>
References: <list-3716481 [at] prxy.net>

At 11:34 AM 6/23/2004, you wrote:
>I am building a basic motion platform, a 4x8 wagon powered by two 3/4 hp 
>motors.  I'm using a PLC from automationdirect, the basic 05 model, to 
>control the motors.  The speed controls I'm using have a 0-10v control 
>circuit, and I want to connect the PLC to this.  I could buy the 
>analog-out option module, but I was wondering if anyone knew how I could 
>go about buying or making a digital to analog converter that would take a 
>signal from the high-speed outputs on the PLC and use it to regulate a 
>current to the speed control.  The resolution wouldn't have to be more 
>than 8 bit, it's not a precision operation.  Thanks.
>
>Ben Kehoe

If you can generate a PWM signal out one of the ports then it's really 
easy.  If not, if you have 8 spare outputs per axis, then go straight to an 
8-bit D/A chip.  Otherwise you could shift out the data using 3 outputs 
(I've done this with the 250 system from Automation Direct).


----------
Jerry Durand
Durand Interstellar, Inc.
219 Oak Wood Way
Los Gatos, California 95032-2523  USA
tel:  +1 408 356-3886
fax:  +1 408 356-4659
web:  www.interstellar.com



------------------------------

From: "Brian Busch" <bpbusch [at] techie.com>
Subject: Re: Cheap D/A circuitry
Date: Wed, 23 Jun 2004 19:18:27 -0400
Message-ID: <000c01c45978$646191c0$0200a8c0 [at] trinity>
In-Reply-To: <list-3717492 [at] prxy.net>

As someone who has used that PLC and others from the wonderful people at
Automation Direct, I would agree with Mark. Their components work
together beautifully (including the Analog out module) and we have used
them reliably multiple times. Furthermore, if you run into trouble with
any component from Automation Direct their technical support is
extremely helpful. 

>>The speed controls I'm using have a 0-10v control circuit......use it
to regulate a current to the speed control.<<

So is your controller looking for variation in voltage or current for
speed control? In either case a module can be had, relatively cheaply,
to provide the proper signals to the motor controller. This is assuming
that the motor controller is looking for a separate direction signal. If
this is not the case the O5 and 06 PLC analog modules are incapable of
providing +/-10V to indicate speed and direction. Building your own may
be the only option to use it with the 05 PLC. (See Jerry's post)

Is this the only scenic unit being controlled by the PLC? If it is, then
you could build a simple interface with a power supply, a few switches
and a pot, leaving the PLC to control only the positioning information
either from an encoder or limit switches. I have found it easier to
implement a PLC into automation if it will be responsible everything.
When you remove speed and direction from the PLC control there is often
little point in using that PLC for any part of the control circuitry.

Remember: Good, Fast or Cheap. Pick two.

Brian Busch



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End of Stagecraft Digest #50
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