Multi-Meter advice...

In the inexpensive do-it-all meters, This One is my pick so far. AC, DC (voltage AND clamp-on amps) plus the usual Ohms, but also capacitance and frequency.

If you look at an internet TV show,, I think it is Ham Nation but it might be Amateurlogic.tv.. Recent (last quarter of last year) George Thomas built and demonstarted a small one-cell LED light I can not recall the name of the kit but it was designed for use in 3rd world countries and takes AA cells that are, shall we say, past their prime.

This is NOT the one George reviewed but sure looks like a basic copy of it..

http://www.instructables.com/id/GEMS-DEAD-BATTERY-FLASH-LIGHT/

After years of struggling to calibrate my multimeters for voltage, I found an $8 voltage reference on ebay from China.
ebay link

It provides a 10.0 volt reference. It came with a calibration record so the seller is at least aware it needs to be checked.

Incidentally, the same seller has a little flashlight with a Cree LED. I've heard folks on RV.net say the Cree is the best, so I bought one of these little 1 AA battery flashlights for $4. I am very impressed with its brightness and apparent quality.
flashlight on ebay

MEXICOWANDERER wrote:
A meter is useless unless the probe tip can pierce PVC or cross-link insulation
Same for clamping a lead to a wire or terminal


The OLDAKER brand test leads with needle-sharp stainless steel tips are without peer in the test lead world. They make a joke out of Fluke test leads.

Regardless butcher your meter when you get it. Fashion a hook from a coat hanger then lay hands on a strong neodmium magnet and GOOP it to the rear side of the case.

Years ago when I was still repairing consumer electronics I took a BIC pen assy. Removed the insides and put a stainless steel antenna rod in it and sharpened the end so I could pierce the coating on circuit boards. I still use it today. I put a bit of braze on the rod so I could solder the probe wire to it.

http://www.dx.com/p/uni-t-ut203-digital-clamp-multimeter-ac-dc-600v-400a-max-15220#.VKnV7Wd0xjp

One thing a clamp on couldn't do is Salvo's way of measuring R on a long wire.

You extend one lead of your multimeter with 30 feet of speaker wire and an alligator clamp on the end of that, then you put that on one end and the other probe on the end where you are thirty feet away so now you can read the voltage off the meter display. You get your current from the Trimetric for what is on that wire (such as from the DC panel battery lugs to the batteries) Then you calculate your R.

Then you post that R and get into fight over spelling Mohms, ohms, and mohms depending on decimal points or the time of day or whatever :)

Here is a multimeter and AC/DC clampmeter available on Amazon for $30.
http://www.dx.com/p/uni-t-ut203-digital-clamp-multimeter-ac-dc-600v-400a-max-15220#.VKnT_FaCOrU

I have a similar one that works well. The DC volt range is accurately calibrated and the DC clampmeter seems to be good down to a quarter of an amp at least. I am very pleased with it. Perfect for RV use.

Back when I was a working stiff, I did a lot of troubleshooting of some pretty high tech electronic equipment. Never needed to poke a hole in the insulation. If I was a automotive type guy, I would have something like THIS to assist me in troubleshooting problems. In fact I do have a similar OBD reader and have diagnosed some problems on my Jeep.

Salvo wrote:
From your comments, I take it you don't do much troubleshooting.

Inserting a needle probe into wire insulation is an excellent way to troubleshoot. For example, in a car, how do you determine if the lambda sensor is functioning with just home mechanic tools? You got to probe the sensor wire.

dons2346 wrote:

An excellent way to create problems down the road. Water can get into the wiring and will cause corrosion which will eat up the wire strands and cause a reduction in current carrying capability.

It might not happen this year or the next but sometime down the line, you will have a corroded wire.

This is not a good troubleshooting technique.

I'm not much good at electronics and I'm not into solar. What I am into is automotive, appliances and air conditioning. A meter like the cheap HF will meet most needs except capacitance. I'm fortunate to also have a Fluke 12 that does capacitance, invaluable in A/C testing. My Ammeter is a cheap AC-only unit form HF. My standby was an old AmProbe that I found out the hard way to be reading only about half the actual current.
So for what I do, I could get away with the HF ammeter and their lowest-priced DVOM that handles capacitance. Or a combo meter with clamp-on AC Amps that also had capacitance. Such meters exist. Getting one that does all that with clamp-on DC Amps is trickier.
A little off topic, but a 12VDC Test Light (ice pick with a test lead out the other end and light in the handle) is essential for automotive. Cheap too.

From your comments, I take it you don't do much troubleshooting.

Inserting a needle probe into wire insulation is an excellent way to troubleshoot. For example, in a car, how do you determine if the lambda sensor is functioning with just home mechanic tools? You got to probe the sensor wire.

dons2346 wrote:

An excellent way to create problems down the road. Water can get into the wiring and will cause corrosion which will eat up the wire strands and cause a reduction in current carrying capability.

It might not happen this year or the next but sometime down the line, you will have a corroded wire.

This is not a good troubleshooting technique.

I have a collection of multi-meters (Hazard of Electroincs as a hobby and being certified in the field).

One is a 50 or 60 dollar Sears job, does everything that meter does, Clamp on AC/DC amps, frequency, capacity, temperature and a couple other tests. (Not sure about battery test though, but then I know how to do that).

Some were gotten at Harbor Freight in the zero to 10 dollar range.

One is a Radio Shack I thin 250 list (Purchesed for less) alas it has a problem, but when new it did everything the Crafstmand did (Temp included) except clamp on.. Fits a FLUKE case like it was designed for it, but something smoked.

One thing you need to know is this,, Meters have error rates,, You need to "calibrate" the meter. Two ways to so this one is to use a reference test device (Example a brand new never been used carbon zinc D Cell) and another is to compare to a known meter... Consistancy is more improtant than accuracy once you know the error rate.

That is if you hook it to a battery that is 12.5 volts, and it shows 12.9,, Consistance = IT WILL ALWAYS show 12.9,, and if you know the error you can ajust. Accuracy (Which also requires consistancy) is showing 12.5.

Which ones do I use the most: Generally the cheaper ones,, why, If they get damaged, no great loss. But when I need it the crafstman is right nice.