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| Michael... |
 Posted: Tue Oct 27, 2009 6:45 pm |
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Guest
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To test a non-starting vehicle's distributor, I need an inductive
ignition tester to see if the central high voltage wire is getting
juice.
Can I whip one up with a simple coil of electromagnet wire (~50
turns), connect to a DMM and place the coil near the HV wire?
Thanks,
Michael |
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| Michael... |
| Posted: Wed Oct 28, 2009 3:17 am |
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On Oct 28, 2:39 am, "Tom Biasi" <tombi... at (no spam) optonline.net> wrote:
[quote]"Michael" <mrdarr... at (no spam) gmail.com> wrote in message
news:27df31ce-3361-436f-89a7-f2179d17be1c at (no spam) v15g2000prn.googlegroups.com...
To test a non-starting vehicle's distributor, I need an inductive
ignition tester to see if the central high voltage wire is getting
juice.
Can I whip one up with a simple coil of electromagnet wire (~50
turns), connect to a DMM and place the coil near the HV wire?
Thanks,
Michael
In the old days we would just hold the wire a little from the engine block
and crank. A spark would jump if it was working. With modern vehicle I
wouldn't do this.
Since you said "distributor" I guess its not a modern vehicle.
Tom
[/quote]
~11 year old truck.
Safe to just hold the wire? Tens of kV arcing through the insulation
won't shock you?
Michael |
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| Michael... |
| Posted: Wed Oct 28, 2009 3:21 am |
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On Oct 28, 5:49 am, N0S... at (no spam) daqarta.com (Bob Masta) wrote:
[quote]On Tue, 27 Oct 2009 21:45:34 -0700 (PDT), Michael
mrdarr... at (no spam) gmail.com> wrote:
To test a non-starting vehicle's distributor, I need an inductive
ignition tester to see if the central high voltage wire is getting
juice.
Can I whip one up with a simple coil of electromagnet wire (~50
turns), connect to a DMM and place the coil near the HV wire?
The spark produces a very narrow spike, so I'm not
sure that a DMM would show it (though I haven't
tried this).
However, if you have a scope you can get away with
far less than 50 turns (say, 8-10) wrapped
directly around the coil wire. Not convenient. I
know, but I couldn't get decent results with even
much larger coils that were simply held near the
wire.
[/quote]
What's the typical current going through a spark plug? Is it in the
milliamp or microamp range?
I'm wondering if this could work:
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=95652
Thanks,
Michael
[quote]
Despite that, I found that I did need to keep the
wrapped wire separate from the others to prevent
it seeing spikes from other wires. Should be no
trouble with the coil wire, though... I was trying
to read one wire out of 4 in a loom.
In an earlier exchange on this topic, where
someone wanted to use a frequency counter to
measure RPM, it was suggested to use a small
series resistor leading to parallel reversed
diodes to limit spikes to +/-0.6 V or so. They
suggested 470 ohms, but I've had good results with
10K. You can use LEDs instead of conventional
diodes to get a bigger signal.
I've been experimenting with this because the next
version of my Daqarta software will include an RPM
mode for the frequency counter, that allows it to
correct for number of cylinders. It actually
measures period and inverts, so you get immediate
high-resolution results.
That version (v5.00) won't be out for a couple of
weeks, but if you just want to monitor the spark
signal you can use the current v4.51. It's got a
free 30-session/30-day trial, which should be more
than enough to test your vehicle. <g
Let me know if there are any questions on how to
use the software. (There's over 500 pages of
built-in Help, but it might be intimidating when
you are just getting started.)
Best regards,
Bob Masta
DAQARTA v4.51
Data AcQuisition And Real-Time Analysis
www.daqarta.com
Scope, Spectrum, Spectrogram, Sound Level Meter
FREE Signal Generator
Science with your sound card![/quote] |
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| Tom Biasi... |
| Posted: Wed Oct 28, 2009 4:39 am |
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Guest
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"Michael" <mrdarrett at (no spam) gmail.com> wrote in message
news:27df31ce-3361-436f-89a7-f2179d17be1c at (no spam) v15g2000prn.googlegroups.com...
[quote]To test a non-starting vehicle's distributor, I need an inductive
ignition tester to see if the central high voltage wire is getting
juice.
Can I whip one up with a simple coil of electromagnet wire (~50
turns), connect to a DMM and place the coil near the HV wire?
Thanks,
Michael
[/quote]
In the old days we would just hold the wire a little from the engine block
and crank. A spark would jump if it was working. With modern vehicle I
wouldn't do this.
Since you said "distributor" I guess its not a modern vehicle.
Tom |
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| Bob Masta... |
| Posted: Wed Oct 28, 2009 7:49 am |
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Guest
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On Tue, 27 Oct 2009 21:45:34 -0700 (PDT), Michael
<mrdarrett at (no spam) gmail.com> wrote:
[quote]To test a non-starting vehicle's distributor, I need an inductive
ignition tester to see if the central high voltage wire is getting
juice.
Can I whip one up with a simple coil of electromagnet wire (~50
turns), connect to a DMM and place the coil near the HV wire?
[/quote]
The spark produces a very narrow spike, so I'm not
sure that a DMM would show it (though I haven't
tried this).
However, if you have a scope you can get away with
far less than 50 turns (say, 8-10) wrapped
directly around the coil wire. Not convenient. I
know, but I couldn't get decent results with even
much larger coils that were simply held near the
wire.
Despite that, I found that I did need to keep the
wrapped wire separate from the others to prevent
it seeing spikes from other wires. Should be no
trouble with the coil wire, though... I was trying
to read one wire out of 4 in a loom.
In an earlier exchange on this topic, where
someone wanted to use a frequency counter to
measure RPM, it was suggested to use a small
series resistor leading to parallel reversed
diodes to limit spikes to +/-0.6 V or so. They
suggested 470 ohms, but I've had good results with
10K. You can use LEDs instead of conventional
diodes to get a bigger signal.
I've been experimenting with this because the next
version of my Daqarta software will include an RPM
mode for the frequency counter, that allows it to
correct for number of cylinders. It actually
measures period and inverts, so you get immediate
high-resolution results.
That version (v5.00) won't be out for a couple of
weeks, but if you just want to monitor the spark
signal you can use the current v4.51. It's got a
free 30-session/30-day trial, which should be more
than enough to test your vehicle. <g>
Let me know if there are any questions on how to
use the software. (There's over 500 pages of
built-in Help, but it might be intimidating when
you are just getting started.)
Best regards,
Bob Masta
DAQARTA v4.51
Data AcQuisition And Real-Time Analysis
www.daqarta.com
Scope, Spectrum, Spectrogram, Sound Level Meter
FREE Signal Generator
Science with your sound card! |
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| Rich Grise... |
| Posted: Wed Oct 28, 2009 10:04 am |
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Guest
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On Tue, 27 Oct 2009 21:45:34 -0700, Michael wrote:
[quote]To test a non-starting vehicle's distributor, I need an inductive ignition
tester to see if the central high voltage wire is getting juice.
Can I whip one up with a simple coil of electromagnet wire (~50 turns),
connect to a DMM and place the coil near the HV wire?
Pull the coil wire off the distributor. Hold the metal contact of the[/quote]
coil wire about 1/2" from the engine block/manifold/whatever, as long
as it's metal and grounded. Crank the engine. If you get an arc, it's
OK, check the cap/rotor/plugs. If not, then it's the coil/points/ballast/
condenser.
Hope This Helps!
Rich |
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| Rich Grise... |
| Posted: Wed Oct 28, 2009 10:10 am |
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On Wed, 28 Oct 2009 06:17:33 -0700, Michael wrote:
[quote]On Oct 28, 2:39 am, "Tom Biasi" <tombi... at (no spam) optonline.net> wrote:
"Michael" <mrdarr... at (no spam) gmail.com> wrote in message
Since you said "distributor" I guess its not a modern vehicle.
~11 year old truck.
Safe to just hold the wire?
[/quote]
Yes.
[quote]Tens of kV arcing through the insulation
won't shock you?
[/quote]
No - that's what the insulation is for. If the voltage gets high enough
to punch through that insulation, it will already have made the arc
to the block. If it doesn't arc, it's because there isn't enough voltage,
therefore not enough to do harm.
And even if you _did_ get zapped, it's WELL below 15 mA, and will give
you a jolt, but non-lethal unless you have a pacemaker or some other
preexisting condition.
Or, you could get a plastic fuse puller and hold the wire with it:
http://www.eclipsetools.com/ProductPics/Latest .jpegs/900-177.JPG
Have Fun!
Rich |
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| David Eather... |
| Posted: Thu Oct 29, 2009 7:16 am |
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Guest
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Michael wrote:
[quote]To test a non-starting vehicle's distributor, I need an inductive
ignition tester to see if the central high voltage wire is getting
juice.
Can I whip one up with a simple coil of electromagnet wire (~50
turns), connect to a DMM and place the coil near the HV wire?
Thanks,
Michael
[/quote]
If you just want yes/no you could test by getting an NE2 neon bulb,
splay the leads out, hold one lead and let the other one rub along the
insulation of the still plugged in HV leads |
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| Bob Masta... |
| Posted: Thu Oct 29, 2009 7:23 am |
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Guest
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On Wed, 28 Oct 2009 09:10:36 -0700, Rich Grise
<richgrise at (no spam) example.net> wrote:
[quote]On Wed, 28 Oct 2009 06:17:33 -0700, Michael wrote:
On Oct 28, 2:39 am, "Tom Biasi" <tombi... at (no spam) optonline.net> wrote:
"Michael" <mrdarr... at (no spam) gmail.com> wrote in message
Since you said "distributor" I guess its not a modern vehicle.
~11 year old truck.
Safe to just hold the wire?
Yes.
Tens of kV arcing through the insulation
won't shock you?
No - that's what the insulation is for. If the voltage gets high enough
to punch through that insulation, it will already have made the arc
to the block. If it doesn't arc, it's because there isn't enough voltage,
therefore not enough to do harm.
And even if you _did_ get zapped, it's WELL below 15 mA, and will give
you a jolt, but non-lethal unless you have a pacemaker or some other
preexisting condition.
Or, you could get a plastic fuse puller and hold the wire with it:
http://www.eclipsetools.com/ProductPics/Latest .jpegs/900-177.JPG
Have Fun!
Rich
[/quote]
Holding the wire with your bare hand can give you
a kick! Been there, done that, lesson learned at
a tender age. With 50,000+ V, especially on old
wires, there will probably always be enough
leakage to give you a poke. I don't think this
necessarily leaky insulation, more likely
conduction along the surface grime and humidity.
May not harm you electrically, but when you jump
you may hit something! You definitely won't try
this twice.
Best regards,
[quote]
[/quote]
Bob Masta
DAQARTA v4.51
Data AcQuisition And Real-Time Analysis
www.daqarta.com
Scope, Spectrum, Spectrogram, Sound Level Meter
FREE Signal Generator
Science with your sound card! |
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| Bob Masta... |
| Posted: Thu Oct 29, 2009 7:26 am |
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Guest
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On Wed, 28 Oct 2009 06:21:54 -0700 (PDT), Michael
<mrdarrett at (no spam) gmail.com> wrote:
[quote]On Oct 28, 5:49=A0am, N0S... at (no spam) daqarta.com (Bob Masta) wrote:
On Tue, 27 Oct 2009 21:45:34 -0700 (PDT), Michael
mrdarr... at (no spam) gmail.com> wrote:
To test a non-starting vehicle's distributor, I need an inductive
ignition tester to see if the central high voltage wire is getting
juice.
Can I whip one up with a simple coil of electromagnet wire (~50
turns), connect to a DMM and place the coil near the HV wire?
The spark produces a very narrow spike, so I'm not
sure that a DMM would show it (though I haven't
tried this).
However, if you have a scope you can get away with
far less than 50 turns (say, 8-10) wrapped
directly around the coil wire. =A0Not convenient. I
know, but I couldn't get decent results with even
much larger coils that were simply held near the
wire.
What's the typical current going through a spark plug? Is it in the
milliamp or microamp range?
I'm wondering if this could work:
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=3D95652
[/quote]
When I go to that link, I get:
"The Specifications for this item are not
currently available online, or the item has been
discontinued"
So I don't think it will work, whatever it is!
Best regards,
Bob Masta
DAQARTA v4.51
Data AcQuisition And Real-Time Analysis
www.daqarta.com
Scope, Spectrum, Spectrogram, Sound Level Meter
FREE Signal Generator
Science with your sound card! |
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| Michael A. Terrell... |
| Posted: Thu Oct 29, 2009 8:53 am |
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Guest
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Bob Masta wrote:
[quote]
On Wed, 28 Oct 2009 06:21:54 -0700 (PDT), Michael
mrdarrett at (no spam) gmail.com> wrote:
On Oct 28, 5:49=A0am, N0S... at (no spam) daqarta.com (Bob Masta) wrote:
On Tue, 27 Oct 2009 21:45:34 -0700 (PDT), Michael
mrdarr... at (no spam) gmail.com> wrote:
To test a non-starting vehicle's distributor, I need an inductive
ignition tester to see if the central high voltage wire is getting
juice.
Can I whip one up with a simple coil of electromagnet wire (~50
turns), connect to a DMM and place the coil near the HV wire?
The spark produces a very narrow spike, so I'm not
sure that a DMM would show it (though I haven't
tried this).
However, if you have a scope you can get away with
far less than 50 turns (say, 8-10) wrapped
directly around the coil wire. =A0Not convenient. I
know, but I couldn't get decent results with even
much larger coils that were simply held near the
wire.
What's the typical current going through a spark plug? Is it in the
milliamp or microamp range?
I'm wondering if this could work:
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=3D95652
When I go to that link, I get:
"The Specifications for this item are not
currently available online, or the item has been
discontinued"
So I don't think it will work, whatever it is!
[/quote]
It was there yesterday. that link was for a sale, and the last five
digits are the stock number. It is a simple clamp on AC ammeter
<http://www.harborfreight.com/cpi/ctaf/displayitem.taf?itemnumber=95652&Submit=Go>
Here is a link to the user manual.
<http://www.harborfreight.com/manuals/95000-95999/95652.pdf>
It isn't designed to read low current pulses. it is for
troubleshooting electrical problems and the lowest AC current range is
200 amps, with a resolution of .1 amp.
That PDF also covers model 42396, which the 95652 replaced.
--
The movie 'Deliverance' isn't a documentary! |
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| Michael A. Terrell... |
| Posted: Thu Oct 29, 2009 9:01 am |
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Guest
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David Eather wrote:
[quote]
Michael wrote:
To test a non-starting vehicle's distributor, I need an inductive
ignition tester to see if the central high voltage wire is getting
juice.
Can I whip one up with a simple coil of electromagnet wire (~50
turns), connect to a DMM and place the coil near the HV wire?
Thanks,
Michael
If you just want yes/no you could test by getting an NE2 neon bulb,
splay the leads out, hold one lead and let the other one rub along the
insulation of the still plugged in HV leads
[/quote]
Just spend a few dollars and buy the right damn tool:
<http://www.jcwhitney.com/SPARK_INDICATOR?ID=12;0;0;0;100001;ProductName;0;0;0;N;2004215;0;0>
$6.99 Lisle Spark Indicator SKU Number: 1JA 508138
Manufacturer's part Number: 19380
--
The movie 'Deliverance' isn't a documentary! |
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| IanM... |
| Posted: Thu Oct 29, 2009 12:42 pm |
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Guest
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Michael A. Terrell wrote:
[quote]David Eather wrote:
Michael wrote:
To test a non-starting vehicle's distributor, I need an inductive
ignition tester to see if the central high voltage wire is getting
juice.
Can I whip one up with a simple coil of electromagnet wire (~50
turns), connect to a DMM and place the coil near the HV wire?
Thanks,
Michael
If you just want yes/no you could test by getting an NE2 neon bulb,
splay the leads out, hold one lead and let the other one rub along the
insulation of the still plugged in HV leads
Just spend a few dollars and buy the right damn tool:
http://www.jcwhitney.com/SPARK_INDICATOR?ID=12;0;0;0;100001;ProductName;0;0;0;N;2004215;0;0
$6.99 Lisle Spark Indicator SKU Number: 1JA 508138
Manufacturer's part Number: 19380
Or a spare spark plug, firmly taped to metal on the block. Cant hurt[/quote]
*any* ignition system to discharge through an appropriately gapped plug.
--
Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED)
ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk
[at]= at (no spam) , [dash]=- & [dot]=. *Warning* HTML & >32K emails --> NUL: |
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| Michael A. Terrell... |
| Posted: Thu Oct 29, 2009 2:20 pm |
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Guest
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IanM wrote:
[quote]
Michael A. Terrell wrote:
David Eather wrote:
Michael wrote:
To test a non-starting vehicle's distributor, I need an inductive
ignition tester to see if the central high voltage wire is getting
juice.
Can I whip one up with a simple coil of electromagnet wire (~50
turns), connect to a DMM and place the coil near the HV wire?
Thanks,
Michael
If you just want yes/no you could test by getting an NE2 neon bulb,
splay the leads out, hold one lead and let the other one rub along the
insulation of the still plugged in HV leads
Just spend a few dollars and buy the right damn tool:
http://www.jcwhitney.com/SPARK_INDICATOR?ID=12;0;0;0;100001;ProductName;0;0;0;N;2004215;0;0
$6.99 Lisle Spark Indicator SKU Number: 1JA 508138
Manufacturer's part Number: 19380
Or a spare spark plug, firmly taped to metal on the block. Cant hurt
*any* ignition system to discharge through an appropriately gapped plug.
[/quote]
If that turns your crank. I prefer to buy or build real tools. An
exposed plug could ignite fuel vapors but it's your face that will
suffer, not mine.
--
The movie 'Deliverance' isn't a documentary! |
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| John Fields... |
| Posted: Sat Nov 14, 2009 9:34 am |
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Guest
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On Thu, 29 Oct 2009 23:16:59 +1000, David Eather <eather at (no spam) tpg.com.au>
wrote:
[quote]Michael wrote:
To test a non-starting vehicle's distributor, I need an inductive
ignition tester to see if the central high voltage wire is getting
juice.
Can I whip one up with a simple coil of electromagnet wire (~50
turns), connect to a DMM and place the coil near the HV wire?
Thanks,
Michael
If you just want yes/no you could test by getting an NE2 neon bulb,
splay the leads out, hold one lead and let the other one rub along the
insulation of the still plugged in HV leads.
[/quote]
---
Definitely not a good idea, since if the reason the thing isn't working
right is because of cracked insulation...
Here's using an NE-2 for that purpose in a better way:
news:mjftf5dd4m6bb2k2b1oue5mdh7rd6akklt at (no spam) 4ax.com
JF |
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