[Diy_efi] 555 timer for injector driver

Astrona amdcpu
Thu Jul 7 11:40:14 UTC 2005


Why not use MOSFETs with driver like they do?
  ----- Original Message ----- 
  From: Bobby Yates Emory 
  To: diy_efi at diy-efi.org 
  Sent: Thursday, July 07, 2005 8:23 AM
  Subject: Re: [Diy_efi] 555 timer for injector driver


  Mark,

  I get the drift that most engines are not precisely timing the moment that an injector is open.  What they are trying to get right is the duty cycle - is it open 40% of the time or 45%?

  If the relay takes an equal length of time to open or close the circuit, its delay would be irrelevant.  If it is faster for one or the other, that will bias the timing, but should be something one can work around - but remember the timing is reversed, because you are using the relay to ground the injector.

  Should allow Jeff to perform his experiment.

  Bobby


  On 7/6/05, mark krawczuk <krawczuk at dodo.com.au> wrote:



    HI , this is as far as i know....

    you have  power ( positive 12 volts) going in one side of injector, then u
    switch the earth side to make the injector open/close.
    u dont need  a relay to drive the injector,  use  the 555 timer  to 
    switch/pulse a  power transistor to switch the injector, cause the relay ,
    if used to switch a injector open for  fuel use will take tooo long.

    i am not sure if the 555 time can switch enough current by itself ???? 

    even though, using a relay to operate injector should work,.

    mark k


    ----- Original Message -----
    From: "jeff matthews" <maple69vt at hotmail.com >
    To: <diy_efi at diy-efi.org>
    Sent: Thursday, July 07, 2005 11:09 AM
    Subject: [Diy_efi] 555 timer for injector driver


    > Hi-
    > To keep my ??? simple,  I built a 555 timer to work on a little 
    > experiment,  I have it energizing the solenoid on a  12v relay, why won't
    > it open and close my injector? (it's just a basic saturated 550cc).  Is
    > there some secret to on making an injector operate? 
    >
    > Like I stated,  this is for an experiment, just thought I could handle
    > making an injector fire on the bench...
    >
    > Best regards,
    > JEFF
    >
    >
    > _______________________________________________ 
    > Diy_efi mailing list
    > Diy_efi at diy-efi.org
    > http://lists.diy-efi.org/mailman/listinfo/diy_efi
    >
    >
    >


    _______________________________________________
    Diy_efi mailing list
    Diy_efi at diy-efi.org
    http://lists.diy-efi.org/mailman/listinfo/diy_efi




  -- 
  Toward freedom,

  Bobby Yates Emory 


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


  _______________________________________________
  Diy_efi mailing list
  Diy_efi at diy-efi.org
  http://lists.diy-efi.org/mailman/listinfo/diy_efi



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


  No virus found in this incoming message.
  Checked by AVG Anti-Virus.
  Version: 7.0.323 / Virus Database: 267.8.9/42 - Release Date: 7/6/2005
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.diy-efi.org/pipermail/diy_efi/attachments/20050707/3b1a6f90/attachment.html 
-------------- next part --------------
No virus found in this outgoing message.
Checked by AVG Anti-Virus.
Version: 7.0.323 / Virus Database: 267.8.9/42 - Release Date: 7/6/2005



More information about the Diy_efi mailing list