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Old 05-21-2012, 09:44 PM   #1
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Default Multimeter testing coilpack

I read and watched YouTube and am still mostly clueless.

Reading that I need to clean oxidation off the tips and not having sandpaper handy, I used a knife to take off a thin layer.

What I believe to be true:
When not touching tips to anything, the gauge reads infinite. Touching the tips should read zero or close to it.

Tested the coils again and had the same results as below, which makes me think at least the left coil is blown. I am not sure how to interpret some of the numbers to see if they are in operating range

For example, if I set the meter to read 2kohms, and it shows ".4699" does that mean 1.4699??
Or if I set it to 2M, and it shows ".1182" wtf does this mean?
Or if I set it to 20K, and it reads "10.294" does it really mean it is reading 10.294Kohms?


I believe tests 1 & 2 of left coil (below) are reading 'infinite.'.


This ---- bewilders me. Please school me.


Quote:
Originally Posted by 94mx5red View Post
Please look at the photos and tell me if I have this contraption set correctly (doubtful).


Here is the test I am doing:


Here are my results:
Left coil:
  1. Nothing
  2. Nothing
  3. .1197
  4. 10.294
Right coil:
  1. .4699
  2. .1182
  3. .1187
  4. 9.93

Tests 3 and 4 on the left:










Tests 1, 2, 3, 4 on right coil:



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Old 05-22-2012, 12:07 AM   #2
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Manual-ranging meters can be difficult to use properly if you're not intimately familiar with their operation. I might suggest that you look into a simple auto-ranging meter. We in The Business use auto-ranging meters almost exclusively, just because they're faster and easier, and you don't really sacrifice any accuracy with them.

http://www.radioshack.com/product/in...dsInSession=1#
http://www.harborfreight.com/5-in-1-...ter-98674.html


That said, with a manual-ranging meter, you set the dial to the value which is closest to, but greater than, the value which you expect to measure. So with that meter you have there, if you anticipate a resistance of 100k on a given circuit, you'd set the dial to the next-highest number, which is 200k. If you expect a voltage of 14v, you'd set it to 20v. And so on.

It's like the Price is Right in reverse. You set the dial to whatever value is closest to, but not less than, the value which you expect to measure. So a setting of 20k means "I can measure values up to, but not greater than, 20k." When dealing with an unknown value, you simply start at the highest dial setting and work your way down.


Quote:
Originally Posted by 94mx5red View Post
For example, if I set the meter to read 2kohms, and it shows ".4699" does that mean 1.4699??
You need to factor in what the multiplier at the right side of the screen says. So in the image below, the reading is 0.4699k, or 469.9 ohms





Quote:
Or if I set it to 2M, and it shows ".1182" wtf does this mean?
In the image below, the reading is 0.1182 megaohms, which is 118.2 kiloohms, or 118,200 ohms. If you switched the dial down one click to 200k, then the display would read "118.2 K"





Quote:
Or if I set it to 20K, and it reads "10.294" does it really mean it is reading 10.294Kohms?
Since the unit of measure on the right is K in the picture you posted, then yes. 10.294 means 10.294k.
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Old 05-22-2012, 07:59 PM   #3
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Props Joe, thanks!

New measurements:

Left coil:
  1. Infinite with setting at 2K (ideal at 1.5Kohms)
  2. Infinite with setting at 20M (ideal at 2.6 Megaohms)
  3. .98megaohms with setting at 20M (ideal at 2.6 Megaohms)
  4. 10.3kohms with setting at 20K (ideal at 10kohms)

Right coil
  1. .47kohms with setting at 2K (ideal at 1.5Kohms)
  2. .99megaohms with setting at 20M (ideal at 2.6 Megaohms)
  3. .99megaohms with setting at 20M (ideal at 2.6 Megaohms)
  4. 9.9kohms with setting at 20K (ideal at 10kohms)

Comparing to this (only diagram I can find on how to test the 99 coils) diagram, I believe I have bad coils causing my no start condition.
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