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diesel tach

ArchiverArchiver Posts: 46,084
edited 2003-12-30 23:22 in General Discussion
Anyone have any ideas how to pickup a signal for a
tach for a diesel. I was thinking of using a hall
effect transducer on the alternator fan blades anyone
have any better ideas.

Thanks Mikey


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Comments

  • ArchiverArchiver Posts: 46,084
    edited 2003-12-28 04:51
    I was thinking on some diesels they used the alternator output as a tach
    source.

    > Anyone have any ideas how to pickup a signal for a
    > tach for a diesel. I was thinking of using a hall
    > effect transducer on the alternator fan blades anyone
    > have any better ideas.
  • ArchiverArchiver Posts: 46,084
    edited 2003-12-28 07:36
    How about a photodiode through the fan blades or reflected
    off them.
    --
    Regards

    Dave Evartt
    American Hovercraft
  • ArchiverArchiver Posts: 46,084
    edited 2003-12-28 10:52
    I had a diesel 20 years ago, and i glued a 1/4" suare magnet on the
    engine pulley, then I fixed a halellement to pick up the signal. it
    nevver faeiled to work.

    Satchid


    --- In basicstamps@yahoogroups.com, Bill Boyer <daweasel@s...> wrote:
    > I was thinking on some diesels they used the alternator output as a
    tach
    > source.
    >
    > > Anyone have any ideas how to pickup a signal for a
    > > tach for a diesel. I was thinking of using a hall
    > > effect transducer on the alternator fan blades anyone
    > > have any better ideas.
  • ArchiverArchiver Posts: 46,084
    edited 2003-12-28 14:24

    Original Message
    From: "satchid23" <satchid@p...>
    To: <basicstamps@yahoogroups.com>
    Sent: Sunday, December 28, 2003 11:52 AM
    Subject: [noparse][[/noparse]basicstamps] Re: diesel tach


    > I had a diesel 20 years ago, and i glued a 1/4" suare magnet on the
    > engine pulley, then I fixed a halellement to pick up the signal. it
    > nevver faeiled to work.
    >
    > Satchid
    >
    >
    > --- In basicstamps@yahoogroups.com, Bill Boyer <daweasel@s...> wrote:
    > > I was thinking on some diesels they used the alternator output as a
    > tach
    > > source.
    > >
    > > > Anyone have any ideas how to pickup a signal for a
    > > > tach for a diesel. I was thinking of using a hall
    > > > effect transducer on the alternator fan blades anyone
    > > > have any better ideas.
    >
    >
    > To UNSUBSCRIBE, just send mail to:
    > basicstamps-unsubscribe@yahoogroups.com
    > from the same email address that you subscribed. Text in the Subject and Body
    of the message will be ignored.
    >
    >
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    >
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    >
    >
    >
  • ArchiverArchiver Posts: 46,084
    edited 2003-12-28 16:03
    --- Dave Evartt <davee@a...> wrote:
    > How about a photodiode through the fan blades or
    > reflected
    > off them.

    I have a question about this...In the few posts about
    the alternator being used as a tach-source, I have to
    wonder, is it turning at the same RPM as the engine?
    On all of my vehicles, it is not, but I don't know
    about this diesel engine.



    =====
    Chris Savage
    Knight Designs
    324 West Main Street
    Montour Falls, NY 14865
    (607) 535-6777

    http://www.knightdesigns.com

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  • ArchiverArchiver Posts: 46,084
    edited 2003-12-28 16:29
    At 08:03 PM 12/27/03 -0800, mike miller wrote:
    >Anyone have any ideas how to pickup a signal for a
    >tach for a diesel. I was thinking of using a hall
    >effect transducer on the alternator fan blades anyone
    >have any better ideas.
    >
    >Thanks Mikey

    Mikey -

    The diesel engines that I've worked with generally drove a tach sender from the
    fuel pump. The tach sender is essentially nothing more than a small PM DC motor.
    When a PM DC motor is spun, it produces a variable voltage which is proportional

    to the shaft speed. Without using an actual tach sender you'd have check the
    RPM vs. DC Voltage output to determine the speed. The DC voltage output could be
    input to a ADC or possibly used with the RCTime command.

    I don't know if the fuel pump runs at a 1 to 1 ratio with the engine or not, but

    I'd guess that it does. I'm sure you'll see if that's not the case by testing.

    Regards,

    Bruce Bates




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  • ArchiverArchiver Posts: 46,084
    edited 2003-12-29 17:04
    Neat, what did you use for glue?

    I didn't think diesel's used spark-plug wires,
    that's why they call them 'diesel' -- it ignites
    the mixture with compression -- and sometimes
    a glow-plug when the engine is cold.

    SO, an 'electric' signal based approach wouldn't
    work with a diesel. The magnet approach of course
    is very clever, and would work on diesel or
    gas engines.

    --- In basicstamps@yahoogroups.com, "satchid23" <satchid@p...> wrote:
    > I had a diesel 20 years ago, and i glued a 1/4" suare magnet on the
    > engine pulley, then I fixed a halellement to pick up the signal. it
    > nevver faeiled to work.
    >
    > Satchid
    >
    >
    > --- In basicstamps@yahoogroups.com, Bill Boyer <daweasel@s...>
    wrote:
    > > I was thinking on some diesels they used the alternator output as
    a
    > tach
    > > source.
    > >
    > > > Anyone have any ideas how to pickup a signal for a
    > > > tach for a diesel. I was thinking of using a hall
    > > > effect transducer on the alternator fan blades anyone
    > > > have any better ideas.
  • ArchiverArchiver Posts: 46,084
    edited 2003-12-29 17:54
    I do not remeber, but I supose 2 component glue will work, loock for
    high temperature glue.

    Satchid


    --- In basicstamps@yahoogroups.com, "Allan Lane" <allan.lane@h...>
    wrote:
    > Neat, what did you use for glue?
    >
    > I didn't think diesel's used spark-plug wires,
    > that's why they call them 'diesel' -- it ignites
    > the mixture with compression -- and sometimes
    > a glow-plug when the engine is cold.
    >
    > SO, an 'electric' signal based approach wouldn't
    > work with a diesel. The magnet approach of course
    > is very clever, and would work on diesel or
    > gas engines.
    >
    > --- In basicstamps@yahoogroups.com, "satchid23" <satchid@p...>
    wrote:
    > > I had a diesel 20 years ago, and i glued a 1/4" suare magnet on
    the
    > > engine pulley, then I fixed a halellement to pick up the signal.
    it
    > > nevver faeiled to work.
    > >
    > > Satchid
    > >
    > >
    > > --- In basicstamps@yahoogroups.com, Bill Boyer <daweasel@s...>
    > wrote:
    > > > I was thinking on some diesels they used the alternator output
    as
    > a
    > > tach
    > > > source.
    > > >
    > > > > Anyone have any ideas how to pickup a signal for a
    > > > > tach for a diesel. I was thinking of using a hall
    > > > > effect transducer on the alternator fan blades anyone
    > > > > have any better ideas.
  • ArchiverArchiver Posts: 46,084
    edited 2003-12-30 21:37
    The glue idea is pretty clever, but I would consider drilling an tapping a
    small hole in the flywheel and using a machine screw to secure a magnet.
    Having the glue let loose at the wrong time (and Murphy say's it will be at
    the WORST possible time) could ruin your whole day.I also seem to remember
    some flywheels already being drilled for balance, so please don't use a BIG
    magnet that would unbalance anything.

    Mike Sokol
    www.modernrecording.com
    mikes@m...


    " One should not increase, beyond what is necessary,
    the number of entities required to explain anything"...
    -William of Occam-


    Original Message
    From: "satchid23" <satchid@p...>
    To: <basicstamps@yahoogroups.com>
    Sent: Monday, December 29, 2003 12:54 PM
    Subject: [noparse][[/noparse]basicstamps] Re: diesel tach


    > I do not remeber, but I supose 2 component glue will work, loock for
    > high temperature glue.
    >
    > Satchid
    >
    >
    > --- In basicstamps@yahoogroups.com, "Allan Lane" <allan.lane@h...>
    > wrote:
    > > Neat, what did you use for glue?
    > >
    > > I didn't think diesel's used spark-plug wires,
    > > that's why they call them 'diesel' -- it ignites
    > > the mixture with compression -- and sometimes
    > > a glow-plug when the engine is cold.
    > >
    > > SO, an 'electric' signal based approach wouldn't
    > > work with a diesel. The magnet approach of course
    > > is very clever, and would work on diesel or
    > > gas engines.
    > >
    > > --- In basicstamps@yahoogroups.com, "satchid23" <satchid@p...>
    > wrote:
    > > > I had a diesel 20 years ago, and i glued a 1/4" suare magnet on
    > the
    > > > engine pulley, then I fixed a halellement to pick up the signal.
    > it
    > > > nevver faeiled to work.
    > > >
    > > > Satchid
    > > >
    > > >
    > > > --- In basicstamps@yahoogroups.com, Bill Boyer <daweasel@s...>
    > > wrote:
    > > > > I was thinking on some diesels they used the alternator output
    > as
    > > a
    > > > tach
    > > > > source.
    > > > >
    > > > > > Anyone have any ideas how to pickup a signal for a
    > > > > > tach for a diesel. I was thinking of using a hall
    > > > > > effect transducer on the alternator fan blades anyone
    > > > > > have any better ideas.
    >
    >
    > To UNSUBSCRIBE, just send mail to:
    > basicstamps-unsubscribe@yahoogroups.com
    > from the same email address that you subscribed. Text in the Subject and
    Body of the message will be ignored.
    >
    >
    > Yahoo! Groups Links
    >
    > To visit your group on the web, go to:
    > http://groups.yahoo.com/group/basicstamps/
    >
    > To unsubscribe from this group, send an email to:
    > basicstamps-unsubscribe@yahoogroups.com
    >
    > Your use of Yahoo! Groups is subject to:
    > http://docs.yahoo.com/info/terms/
    >
    >
  • ArchiverArchiver Posts: 46,084
    edited 2003-12-30 23:13
    Actually at www.allegromicro.com they have a bunch of different kinds of
    hall effect sensors that work off the ferrous metal gear teeth.
    For example: http://www.allegromicro.com/datafile/archive/3046.pdf
    With one of these you could count the teeth as they pass by the sensor.
    Thus, if you can reach the starter ring gear or some other geared
    sprocket on the engine, you could use one of these to count the tics and
    get revolution information.
    The mounting bolts or screws would work well too, as the screw or bolt
    passed by the sensor it would count the tics too.
    I used one of these on a vibration damper like pulley on the front of an
    engine once. It was held on with four bolts. The sensor would count 4
    tics per revolution of the pulley unit.
    On the small lawn mower engines, they use a aluminum flywheel magneto
    unit. The regular hall effect sensor picks up the magnet on each
    revolution giving a good rpm count method too.

    Original Message
    From: Mike Sokol [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=2Kid60Mohysi0KOgbxzo6AnmkAbyD0hhsZs3P1pPt55EK9mwpT0uW5yNDIV7RgKuXzcKQD57vsMlk52kzqP1]mike.sokol@m...[/url
    Sent: Tuesday, December 30, 2003 3:38 PM
    To: basicstamps@yahoogroups.com
    Subject: Re: [noparse][[/noparse]basicstamps] Re: diesel tach

    The glue idea is pretty clever, but I would consider drilling an tapping
    a
    small hole in the flywheel and using a machine screw to secure a magnet.
    Having the glue let loose at the wrong time (and Murphy say's it will be
    at
    the WORST possible time) could ruin your whole day.I also seem to
    remember
    some flywheels already being drilled for balance, so please don't use a
    BIG
    magnet that would unbalance anything.

    Mike Sokol
    www.modernrecording.com
    mikes@m...


    " One should not increase, beyond what is necessary,
    the number of entities required to explain anything"...
    -William of Occam-


    Original Message
    From: "satchid23" <satchid@p...>
    To: <basicstamps@yahoogroups.com>
    Sent: Monday, December 29, 2003 12:54 PM
    Subject: [noparse][[/noparse]basicstamps] Re: diesel tach


    > I do not remeber, but I supose 2 component glue will work, loock for
    > high temperature glue.
    >
    > Satchid
    >
    >
    > --- In basicstamps@yahoogroups.com, "Allan Lane" <allan.lane@h...>
    > wrote:
    > > Neat, what did you use for glue?
    > >
    > > I didn't think diesel's used spark-plug wires,
    > > that's why they call them 'diesel' -- it ignites
    > > the mixture with compression -- and sometimes
    > > a glow-plug when the engine is cold.
    > >
    > > SO, an 'electric' signal based approach wouldn't
    > > work with a diesel. The magnet approach of course
    > > is very clever, and would work on diesel or
    > > gas engines.
    > >
    > > --- In basicstamps@yahoogroups.com, "satchid23" <satchid@p...>
    > wrote:
    > > > I had a diesel 20 years ago, and i glued a 1/4" suare magnet on
    > the
    > > > engine pulley, then I fixed a halellement to pick up the signal.
    > it
    > > > nevver faeiled to work.
    > > >
    > > > Satchid
    > > >
    > > >
    > > > --- In basicstamps@yahoogroups.com, Bill Boyer <daweasel@s...>
    > > wrote:
    > > > > I was thinking on some diesels they used the alternator output
    > as
    > > a
    > > > tach
    > > > > source.
    > > > >
    > > > > > Anyone have any ideas how to pickup a signal for a
    > > > > > tach for a diesel. I was thinking of using a hall
    > > > > > effect transducer on the alternator fan blades anyone
    > > > > > have any better ideas.
    >
    >
    > To UNSUBSCRIBE, just send mail to:
    > basicstamps-unsubscribe@yahoogroups.com
    > from the same email address that you subscribed. Text in the Subject
    and
    Body of the message will be ignored.
    >
    >
    > Yahoo! Groups Links
    >
    > To visit your group on the web, go to:
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    >
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    >
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    >
    >



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  • ArchiverArchiver Posts: 46,084
    edited 2003-12-30 23:22
    Hi

    I have seen in some old cars, they used an AC output of the generator

    for a diesel tach.



    Heinz

    Original Message
    From: Mike Sokol
    To: basicstamps@yahoogroups.com
    Sent: Tuesday, December 30, 2003 10:37 PM
    Subject: Re: [noparse][[/noparse]basicstamps] Re: diesel tach


    The glue idea is pretty clever, but I would consider drilling an tapping a
    small hole in the flywheel and using a machine screw to secure a magnet.
    Having the glue let loose at the wrong time (and Murphy say's it will be at
    the WORST possible time) could ruin your whole day.I also seem to remember
    some flywheels already being drilled for balance, so please don't use a BIG
    magnet that would unbalance anything.

    Mike Sokol
    www.modernrecording.com
    mikes@m...


    " One should not increase, beyond what is necessary,
    the number of entities required to explain anything"...
    -William of Occam-


    Original Message
    From: "satchid23" <satchid@p...>
    To: <basicstamps@yahoogroups.com>
    Sent: Monday, December 29, 2003 12:54 PM
    Subject: [noparse][[/noparse]basicstamps] Re: diesel tach


    > I do not remeber, but I supose 2 component glue will work, loock for
    > high temperature glue.
    >
    > Satchid
    >
    >
    > --- In basicstamps@yahoogroups.com, "Allan Lane" <allan.lane@h...>
    > wrote:
    > > Neat, what did you use for glue?
    > >
    > > I didn't think diesel's used spark-plug wires,
    > > that's why they call them 'diesel' -- it ignites
    > > the mixture with compression -- and sometimes
    > > a glow-plug when the engine is cold.
    > >
    > > SO, an 'electric' signal based approach wouldn't
    > > work with a diesel. The magnet approach of course
    > > is very clever, and would work on diesel or
    > > gas engines.
    > >
    > > --- In basicstamps@yahoogroups.com, "satchid23" <satchid@p...>
    > wrote:
    > > > I had a diesel 20 years ago, and i glued a 1/4" suare magnet on
    > the
    > > > engine pulley, then I fixed a halellement to pick up the signal.
    > it
    > > > nevver faeiled to work.
    > > >
    > > > Satchid
    > > >
    > > >
    > > > --- In basicstamps@yahoogroups.com, Bill Boyer <daweasel@s...>
    > > wrote:
    > > > > I was thinking on some diesels they used the alternator output
    > as
    > > a
    > > > tach
    > > > > source.
    > > > >
    > > > > > Anyone have any ideas how to pickup a signal for a
    > > > > > tach for a diesel. I was thinking of using a hall
    > > > > > effect transducer on the alternator fan blades anyone
    > > > > > have any better ideas.
    >
    >
    > To UNSUBSCRIBE, just send mail to:
    > basicstamps-unsubscribe@yahoogroups.com
    > from the same email address that you subscribed. Text in the Subject and
    Body of the message will be ignored.
    >
    >
    > Yahoo! Groups Links
    >
    > To visit your group on the web, go to:
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    >
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    >
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    >
    >



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