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Posted by: euro911 Feb 25 2012, 02:20 PM

I just purchased a new 1844 'Ignitor' module. I read the instructions and installed it in the distributor.

I attempted to test the module with a Fluke VOM to verify it provides a pulse. I get a continuous reading of .2387 meg-ohms and the value does not change when the shaft is rotated by hand (yes, magnetic trigger ring is completely seated on the cam shaft).

Does the module require 12vDC to see a pulse? ... or is it possible that this module is defective out of the box?

Posted by: rdauenhauer Feb 25 2012, 08:46 PM

here is a note I wrote


Attached thumbnail(s)

Posted by: euro911 Feb 26 2012, 01:16 AM

So it does need to be powered ... makes sense. I'd like to test it prior to installing on the engine. Thanks, Rich

Posted by: underthetire Feb 26 2012, 03:16 PM

It's might be tough to really see with that old fluke. Analog or true rms meters might show up better.

Posted by: euro911 Feb 27 2012, 04:17 AM

Hey, don't be ragging on my trusty old Fluke

I'll be able to see it pulse if it's rotated slowly

Posted by: 76-914 Feb 27 2012, 09:26 AM

I agree w/ that test except IIRC, the acceptable drop was 0-3v DC.

Posted by: underthetire Feb 27 2012, 09:59 AM

er, probably not. There is a minimum speed to trigger the Pert.
And that is a old Fluke. Havn't seen one since the late 80's like that

Posted by: Tom Feb 27 2012, 10:16 AM

I am certainly no expert, but points work just the opposite of what that test would indicate. You are basically measuring across the switch for voltage/no voltage. With the switch closed = no voltage, switch open = voltage.
When the rotor opens the points you would read voltage and that is when the coil fires. This test would indicate just the opposite.??
Tom

http://www.google.com/url?sa=t&rct=j&q=testing%20pertronix%20ignitor&source=web&cd=2&sqi=2&ved=0CDgQFjAB&url=http%3A%2F%2Fwww.ttalk.info%2FTech%2Fpertronix_igniters.htm&ei=Aa9LT-2UI-GhiQKD0vHaDQ&usg=AFQjCNG5_jOPkWcTdHlBkzppF8B3AYlg3A
Edit: googling found this.

Posted by: euro911 Feb 27 2012, 04:29 PM

Yep, it's actually a late '70's ~ early '80's VOM, but I like it

The plan was just to bench test the Pertronix, prior to installing in the car.


Looking at Rich's sketch, it appears that with 12v applied to the module, the magnetic ring passing over the module's trigger point should provide a changing continuity reading. I agree that an analog VOM would display pulses better, but rotating by hand slowly should provide verification that the unit works.

I don't know for sure (yet), but I can't see rotational speed being an issue ... I'll post my findings later this evening (unless someone else beats me to it) ...

Posted by: Tom Feb 27 2012, 07:21 PM

Mark,
Check step #5 in the link above under negative ground testing.
As the magnetic sleeve is rotated around the pick up, the voltage will vary from 12 to 0 volts.
Tom

Posted by: euro911 Feb 27 2012, 11:08 PM

Aha

Why PerTronix doesn't provide that info with their product is beyond me

Thanks for the link, Tom