Recommendations for volt meter

smkettner wrote:
So what is the fix? Replace the alternator? Seems odd to cause transmission problems.

If you run on pure battery power does that fix the issue?

I wonder if MEX has any ideas.

I was thinking the same thing. OP, give mex some time to chime in. I'd wager he would have an idea of what you're looking for or may have an easier way to Check it. Or(lol) may just say not to worry.

Probably a good ol' alternator whine choke kit ?

So what is the fix? Replace the alternator? Seems odd to cause transmission problems.

If you run on pure battery power does that fix the issue?

I wonder if MEX has any ideas.

What you should be using is a scope to measure this and to see what it is you're looking at. It wouldn't even occur to me to look at ripple down this low with a DVM. I would be way more concerned about lead noise corrupting the reading.

path1 wrote:
Op here...

I'm just trying to test my alternator with the right thing.

"Normal good alternator is 0.01 to 0.03 AC volts. Marginal is 0.05 AC volts. Then a complete fail is 0.1 and above"

Thanks

Be happy. Don't worry.

Not sure where that advice originally came from, but it's not anything to worry about as far as charging or battery life. More of an indication that the alternator/voltage regulator is going bad than anything. Might cause a whine in your stereo, though.

You know those "rejuvenator" chargers? Most of them "work" by imposing an AC signal on the charging voltage. It's debatable whether they work, but it doesn't hurt anything.

Op here...

I'm just trying to test my alternator with the right thing.

"Normal good alternator is 0.01 to 0.03 AC volts. Marginal is 0.05 AC volts. Then a complete fail is 0.1 and above"

Thanks

Harvard wrote:

Yes, I see that you are trying to verify the AC ripple riding on the DC Volts.

I realize I could be wrong about this statement, but instinctively I wouldn't trust anything other than an oscilloscope for this job, or a meter made specifically to measure ripple if there is such a thing. The OP is trying to measure less than 1% ripple.

Harvard wrote:
On the AC Volts range with the probes shorted together the meter reads 0.022 VAC when ideally it should read 0.00 VAC.

That seems high. My ancient Fluke 87 shows 1-2 mV with the leads shorted. And, that's to be expected with wire leads - they'll pick up whatever random RF is floating around. To get closer requires a "relative" measurement function, which puts you into the 87V/287 ($400-600) range.

To the OP:

The Harbor Freight ones aren't bad for what they cost (!), and are handy for basic wiring needs - if you break one, go get another. But IMO, if you want a reliable meter you can trust to be accurate and which will last, look to Fluke or HP/Agilent/Keysight. You can get a Fluke 106 for <$100, and a 113 for not much more (113 doesn't do amps).

Depends on how you are about tools. Do you buy hammers from the $1 bin, or do you buy an Estwing?

Try Extech Instruments. I have one of their units and it will measure down that low.

You should be able to get one for right around $100.