Subject: RE: Aberdeen Bridge Test
Date: Mon, 31 Jan 2000 08:37:21 -0600
From: "Kaufman, Tom" <Tom.Kaufman@mts.com>
To: "Larson, Rod" <Rod.Larson@mts.com>

Thanks Rod:
Questions:  Analog:  To calibrate the stroke, do you scale the A/D in
the ADDA card?  We can get zero of transducer to be at one end, and Full
scale being 42".  Or we can get zero being mid-point of travel(+/-21
travel).  My thought is to get zero at one end, and 10 volt being 42".
Comments?

I left David Chua a message.  Tom Kaufman

> -----Original Message-----
> From: Rod Larson [SMTP:rod.larson@mts.com]
> Sent: Saturday, January 29, 2000 2:47 AM
> To:   Kaufman, Tom
> Subject:      Re: Aberdeen Bridge Test
>
> Tom,
> OK for 3rd 497 rack for 497.15s.  We did 16 valves for NIED S/V
> Controller
> and had room.  I will ck my layout that I just sent to Don Johnson,
> but I
> think it will still work.  I did not specify which Temposonic to use,
> cuz
> the analog can plug directly into ADDA Card (A/D Converter) or Digital
> one
> can go to special ADDA Card.  The analog is much easier cuz it could
> have
> 18 channels on 3/4 of one adda card.  If we use digital, we can ONLY
> get 8
> channels per ADDA Card.  Therefore it would require 2 extra ADDA cards
> and
> Tempo interfaces (about $3,000).  You decide.  I do not think that we
> will
> be using the stroke for control except for set-up; mainly read-out of
> position for max deflections.  Ck w/ David Chua cuz he used an analog
> Tempo
> but I do not think he had any problems that would reflect a problem on
> a
> low frequency system.  (so, for the moment, I vote analog).
>
> Does the 90 GPM valve present a problem for the pump???  Or, can we
> get
> enough accumulator to be ok.
>
> Rod
>
> At 05:51 PM 1/28/00 -0600, you wrote:
> >Rod:
> >The loading curves you did for me have an important piece of
> >information.  It shows the rise time(velocity) needed for each of the
> >actuators.
> >This servo-valve flow is then easy to find.  My conclusion is that
> the
> >60 GPM Moog valves would be too small.
> >They would almost meet the flow for tension side, but the flow out of
> >the compression side would cause too high of a pressure drop over the
> >S/v.  (If we slowed down the time for center cycles, we push the
> higher
> >velocity cycles outward toward ends(with shorter strokes).  We still
> end
> >up with higher velocities than the 60 GPM valve can handle).
> >
> >Therefore I would like to use the normal 90 GPM 256.09.  I did my
> best
> >to check the costs, and it looks like we can save over 10K by using
> the
> >bigger valves.  It means that you will need to use (18) 497.15 valve
> >drivers, and this adds one more 497.01 chassis.  I looked at a normal
> >vertical rack, and it looks like we still have plenty of room for (4)
> >497.01 chassis and the 498 box.  Let me know if you see something
> that
> >is a show-stopper.
> >On Monday next week, I plan to give the actuator group the go-ahead
> to
> >complete BOM's with the 256.09 valve.
> >
> >Another issue:  What temposonic do you want in the actuator.
> >Digital--or analog?  When I did my count of transducer modules, I
> >assumed we would have a module for the tempo, but I did not know if
> this
> >is really needed.  What is really needed????   If digital, do we need
> >any 497 module?
> >Tom K.
> >
