What setting to use on multimeter

[Super]

To all the electrical gurus out there...for the life of me I just can't figure out how to set my multimeter in order to check a reg/rec no matter how many times I read the dang book.

It's an Etek model#10709. What it says is to set it to diode mode and then connect the leads to the appropriate tabs. When I follow the stator papers and try this, I get readings of 577 to 579 on all 3 tabs. But the diode setting has no variables to get a voltage reading.

I'm not an idiot but this is making me feel and look like one! Help please!

[BassCliff]

Hi,

Those numbers are giving you the forward voltage drop of the diodes being tested. Diodes are supposed to conduct electricity in one direction but not in another. If you set your meter to ohms and test again you will find that the diodes in the rectifier portion of the r/r will have almost no resistance in one direction and, after reversing the leads, an infinite resistance (OL) in the other.

I tested one of my good r/r units recently and documented the results.

Regulator/Rectifier Diode Test


Thank you for your indulgence,

BassCliff

[koolaid_kid]

Those readings are in millivolts. So you are actually seeing 0.577 to .579 volts.

[5azzmonkey]

Try reading/viewing these to give yourself some better basic understanding of a multimeter:

http://www.idealindustries.com/media/pdfs/products/guides/basics_of_digital_multimeters.pdf

http://www.youtube.com/watch?v=4VeNiYxiisI

Thanks,
Dave

[BassCliff]

Hi,

Those readings are in millivolts. So you are actually seeing 0.577 to .579 volts.

Yes, the current provided by the meter is not a lot so it's typical to be a little less than the "normal" drop of 0.7v for silicon parts.


Thank you for your indulgence,

BassCliff

[Steve]

Those readings are fine. Now, to finish the test, reverse the leads. Put the red lead where the black one was and the black one where the red one was. You should read ZERO or OL (for OverLoad) or OR (for Over Range).

To do the full diode test for the R/R, you will do a total of TWELVE readings. There are SIX diodes, and you will check each of them in both directions.

You should have SIX readings similar to the two that you just showed, and SIX readings that are not. If you have any other mix of readings, replace the R/R.

.

[koolaid_kid]

Steve, it depends on the meter. My Craftsman 821140 reads 1 instead of OL. Not that I like it, but that is what it does.

[Super]

OK, the wires going from eft to right of reg/rec are B/W, Y, W/Bl, W/R and R.

I'm testing this reg/rec out of the bike, that's right...right?

Ok, So When I put the red lead on the far left tab and check the 4 tabs going to my right, I get 569, 571, 577 and 800.

When I swap the leads and have the black lead on the left tab and use the red lead for readings, I get all 1's..where does that leave me so far?

[Super]

Steve, How do I hook up the leads to get all 12 readings? Just keep alternating the leads on all the tabs of the reg/rec?

[koolaid_kid]

3 of those wires go to the stator. They are involved in every test.
1 is the ground. You test the ground on each of the stator wires, forward and backward.
1 wire is the output voltage. You test is on each of the stator wires, forward and backward.
That is a total 12 tests.

[Super]

Basscliff, You mention switching the meter to ohms. I have the following settings on the ohms side of the multimeter: 20m, 2m, 200k, 20k, 2k, and 200. Which one should I use? Thanks

[cowboyup3371]

You'll want to use the 200 setting.

[Super]

Koolaid Kid...so I need to have the r/r in the bike and hooked up to the stator to do these tests? I currently have the r/r out of the bike.

[BassCliff]

Hi,

Basscliff, You mention switching the meter to ohms. I have the following settings on the ohms side of the multimeter: 20m, 2m, 200k, 20k, 2k, and 200. Which one should I use? Thanks

20m = 20,000,000 ohms (or less)
2m =2,000,000 ohms
200k=200,000 ohms
20k = 20,000 ohms
2k = 2,000 ohms
200 = 200 ohms

Isn't there a "20" setting too, for 20 ohms?

When checking resistance, if your meter shows "OL" (or whatever designates 'out of range' on your meter) just go up to a higher range. Use the lowest range possible for greater accuracy.

When testing the r/r I like using both the diode setting and checking the diodes for resistance just to make sure they are conducting in one direction only. The tests I linked to earlier on my website were done out of the bike.


Thank you for your indulgence,

BassCliff

[Super]

Basscliff, I had to go up to 20m to get a reading. When I hook the red lead to the left tab I get readings of 4.4, 3.8 and 3.5 and these readings deem to fluctuate up and down some.

When I switch the black lead to the left tab I get all 1's..which is the over range reading I believe.