Matronics Email Lists :: View topic

Matronics Email Lists
Web Forum Interface to the Matronics Email Lists

Get Email Distribution Too! FAQ Search Memberlist Usergroups Register

Profile Log in to check your private messages Log in

IVOPROP

Matronics Email Lists Forum Index -> AeroElectric-List

View previous topic :: View next topic

Author Message

nuckolls.bob(at)aeroelect
Guest

Posted: Fri Apr 10, 2009 7:06 am Post subject: IVOPROP

Ron: When the system is not being used it is 3 amp.



     BN: What is drawing current when the prop pitch motor

     is not running?



Ron: This is a good questions but I do not have an answer for it.

      3 x 8 = 24 amp when the circuit breaks. Reaches the stop at 15 amp.



   BN: I'm still trying to understand the amount of

   energy required to satisfy in-flight operating

   requirements. It would stand to reason that

   normal running currents (motor in motion and

   free of the mechanical stops) are a small

   fraction of stall current (motor energized

   but prevented of motion because it is

   jammed).



   Hmmmm . . . I take it you are not the designer

   for this product's electrics. Can I have some

   conversation with the designer or at least someone

   who has understanding of the physics of this

   system?



   I'm thinking there are easy things you can do

   electronically to improve on the system's

   integrity and eliminate installation variability/

   error to achieve advertised performance.



Ron: I found the system is using 3 amps when there is no load on the spool.

This is when it goes through neutral transition between positive pitch

and negative pitch from neutral. When the switch is not used there is no

current.



The designer has moved to a remote secluded location where he can

work on other inventions without any distractions. That is why I

am doing my best to answer your questions without bothering him.

There are no plans to change or modify our propeller design at this time.



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



    Okay, based on this limited exchange I have to deduce

    that the gentleman has but a rudimentary knowledge

    of how the product works. He is unable to discuss

    the physics of the motor's performance at or near

    stall with any notions of improving on user-

    friendliness. One noteworthy design goal would be

    to eliminate the requirement for fine tuning the

    resistance in hookup wire and/or sizing a specific

    style of breaker. This feature alone would get

    him tossed out of a design review meeting at

    any of the places I've worked.



    My best guess is that the motor draws 3A at

    the "no-load" point roughly centered on min-

    max prop pitch. Departures either direction

    from neutral winds up the springs causing motor

    current to rise.  Peak current happens at

    some point just before the system hits the

    mechanical stops. There is no current draw

    when the motor is not running.



    This all makes sense. What does not make sense

    is the tailoring of total loop resistance

    by selection of wire and tailoring of a specific

    circuit breaker to achieve a "safe" reaction

    to an overload.



    Of course, none of this speaks to mechanical

    issues in this product's design. It does give one

    pause to consider the effectiveness of product

    support when difficulties are identified in

    the field. It's also alarming that the designer

    finds it necessary to become secluded from the

    customers that need a better understanding of

    product characteristics than can be offered by

    the present spokesperson.



        Bob . . .



        ----------------------------------------)

        ( . . .  a long habit of not thinking   )

        ( a thing wrong, gives it a superficial )

        ( appearance of being right . . .       )

        (                                       )

        (                  -Thomas Paine 1776-  )

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

- The Matronics AeroElectric-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List

jcorner(at)shaw.ca
Guest

Posted: Fri Apr 10, 2009 8:43 am Post subject: IVOPROP

Bob



I have used all three models of IVO Props over the years, and I like  

the design because of the simplicity and cost.



The attached PDF shows the construction of the prop hub and the wiring  

that controls it.

I have found that if the toggle switch is held after the prop hits the  

mechanical  stops the circuit breaker will pop regardless of the  

length of wire.



The best method of setting prop pitch in the air or on the ground is  

to use an ammeter in series rather than just watching RPM's.  This  

also can prevent  breaker tripping.  The problem here is finding a  

suitably scaled ammeter, in a compact size. Anyone?



I have trimmed the wire length to what is required in two out of three  

installations without any apparent adverse effect.



Jim



On 10-Apr-09, at 9:06 AM, Robert L. Nuckolls, III wrote:



 	  Quote: 	
		   

 >



 Ron: When the system is not being used it is 3 amp.



    BN: What is drawing current when the prop pitch motor

    is not running?



 Ron: This is a good questions but I do not have an answer for it.

     3 x 8 = 24 amp when the circuit breaks. Reaches the stop at 15  

 amp.



  BN: I'm still trying to understand the amount of

  energy required to satisfy in-flight operating

  requirements. It would stand to reason that

  normal running currents (motor in motion and

  free of the mechanical stops) are a small

  fraction of stall current (motor energized

  but prevented of motion because it is

  jammed).



  Hmmmm . . . I take it you are not the designer

  for this product's electrics. Can I have some

  conversation with the designer or at least someone

  who has understanding of the physics of this

  system?



  I'm thinking there are easy things you can do

  electronically to improve on the system's

  integrity and eliminate installation variability/

  error to achieve advertised performance.



 Ron: I found the system is using 3 amps when there is no load on the  

 spool.

 This is when it goes through neutral transition between positive pitch

 and negative pitch from neutral. When the switch is not used there  

 is no

 current.



 The designer has moved to a remote secluded location where he can

 work on other inventions without any distractions. That is why I

 am doing my best to answer your questions without bothering him.

 There are no plans to change or modify our propeller design at this  

 time.



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



   Okay, based on this limited exchange I have to deduce

   that the gentleman has but a rudimentary knowledge

   of how the product works. He is unable to discuss

   the physics of the motor's performance at or near

   stall with any notions of improving on user-

   friendliness. One noteworthy design goal would be

   to eliminate the requirement for fine tuning the

   resistance in hookup wire and/or sizing a specific

   style of breaker. This feature alone would get

   him tossed out of a design review meeting at

   any of the places I've worked.



   My best guess is that the motor draws 3A at

   the "no-load" point roughly centered on min-

   max prop pitch. Departures either direction

   from neutral winds up the springs causing motor

   current to rise.  Peak current happens at

   some point just before the system hits the

   mechanical stops. There is no current draw

   when the motor is not running.



   This all makes sense. What does not make sense

   is the tailoring of total loop resistance

   by selection of wire and tailoring of a specific

   circuit breaker to achieve a "safe" reaction

   to an overload.



   Of course, none of this speaks to mechanical

   issues in this product's design. It does give one

   pause to consider the effectiveness of product

   support when difficulties are identified in

   the field. It's also alarming that the designer

   finds it necessary to become secluded from the

   customers that need a better understanding of

   product characteristics than can be offered by

   the present spokesperson.



       Bob . . .



       ----------------------------------------)

       ( . . .  a long habit of not thinking   )

       ( a thing wrong, gives it a superficial )

       ( appearance of being right . . .       )

       (                                       )

       (                  -Thomas Paine 1776-  )

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

- The Matronics AeroElectric-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List

Ivo_Mag_PDF003.pdf

Description:

Download

Filename:

Ivo_Mag_PDF003.pdf

Filesize:

819.04 KB

Downloaded:

312 Time(s)

nuckolls.bob(at)aeroelect
Guest

Posted: Fri Apr 10, 2009 10:33 am Post subject: IVOPROP

At 11:40 AM 4/10/2009, you wrote:

 	  Quote: 	
		  Bob



I have used all three models of IVO Props over the years, and I like

the design because of the simplicity and cost.



The attached PDF shows the construction of the prop hub and the wiring

that controls it.

I have found that if the toggle switch is held after the prop hits the

mechanical  stops the circuit breaker will pop regardless of the

length of wire.



The best method of setting prop pitch in the air or on the ground is

to use an ammeter in series rather than just watching RPM's.  This

also can prevent  breaker tripping.  The problem here is finding a

suitably scaled ammeter, in a compact size. Anyone?


	


   Perhaps one of these paired with the appropriate shunt

   sized for max load?



https://matronics.com/aeroelectric/Catalog/AEC/9007/9007.html

 	  Quote: 	
		  I have trimmed the wire length to what is required in two out of three

installations without any apparent adverse effect.


	


   I would have guessed that . . .



   I've designed actuator control systems designed to

   limit travel with hard stops as opposed to limit

   switches. One technique involves a small constant

   current limit module that allows one a few percent

   more than max operating current to flow. This value

   is generally well under the value of the protective

   circuit breaker. Further, performance in both normal

   and fault modes is independent of breaker or wire

   selection.



   If you'd like to experiment with such a system, I'd

   be pleased to support the effort with a proof

   of concept limiter.



   Another option would be to evaluate the polyswitch.

   It's successful incorporation would emulate the

   electric window risers on most cars. Those systems

   don't have limit switches either. They depend on

   operator response to release the switch in some

   reasonable time after window limits are reached.

   But if the operator is slow, the mechanism jams

   or the switch sticks, the polyswitch keeps all

   the smoke inside the wires.



   This product's relative success in the field shows

   a lot of promise. It's too bad that the business

   model for its production is not more conducive

   to the fine tuning of a recipe for success.



        Bob . . .



        ----------------------------------------)

        ( . . .  a long habit of not thinking   )

        ( a thing wrong, gives it a superficial )

        ( appearance of being right . . .       )

        (                                       )

        (                  -Thomas Paine 1776-  )

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

- The Matronics AeroElectric-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List

Display posts from previous:

	Matronics Email Lists Forum Index -> AeroElectric-List	All times are GMT - 8 Hours
Page 1 of 1

Jump to:

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum