Re: [DMCForum] crush washers on the fuel distributor
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [DMCForum] crush washers on the fuel distributor



> Ever
> notice a ceiling fan Humm that has a variable speed
control as the voltage
> is turned down.All electric motors will do this

When my fuel pump gets noisy (even happens with moderately
warm fuel now), the pitch (not necessarily volume) changes
according to system voltage.

John, you are correct that motors running on insufficient
voltage may make more noise, but your example is wrong.  A
ceiling fan will make more noise when fed through a variable
speed control because of what the control does.  It does not
actually lower voltage (peak, not average).  Instead it has
a switching transistor that rapidly switches the voltage
on/off.  The potentiometer varies the duty cycle that the
transistor switches at.  The lower the duty cycle, the
slower & noisier the fan is.  This technique when used in
light dimmers also can also make light bulb filaments noisy.

That's your electronics lesson for the day.

Walt



To unsubscribe from this group, send an email to:
DMCForum-unsubscribe@xxxxxxxxxxxxxxx





  _____  

Yahoo! Groups Links


*	To visit your group on the web, go to:
http://groups.yahoo.com/group/DMCForum/
  

*	To unsubscribe from this group, send an email to:
DMCForum-unsubscribe@xxxxxxxxxxxxxxx
<mailto:DMCForum-unsubscribe@xxxxxxxxxxxxxxx?subject=Unsubscribe> 
  

*	Your use of Yahoo! Groups is subject to the Yahoo! Terms of
Service <http://docs.yahoo.com/info/terms/> . 


<<attachment: winmail.dat>>



Home Back to the Home of PROJECT VIXEN 


Copyright ProjectVixen.com. All rights reserved.

Opinions expressed in posts reflect the views of their respective authors.
DMCForum Mailing List Archive  DMCNews Mailing List Archive  DMC-UK Mailing List Archive

This site contains affiliate links for which we may be compensated