Thoughts for a half decent multimeter??

[tatu]

I was faced with a similar situation a couple of years ago. However, I found a similar meter at Radio Shack before I saw the one at Sears. It was $80, and the only apparent difference is a third amp scale that covers 800 amps.

The test equipment at work has to be calibrated every year (we verify accuracy on medical equipment). When the crew came through to do the shop equipment, I had them run the Radio Shack meter across their tester to see how it fared. I did not ask for a sticker that verified accuracy, so they did it at no charge. On the 40 amp scale, 30 amps showed on the meter as 28. On the 400 amp scale, 300 amps showed as 320. Those were the only two items that would have made it not earn a sticker, but they are close enough for the work that I do on the bikes. For the stuff at work, I use the 30 (or so) year old Fluke 77 that still passes calibration every year.

Since Radio Shack has all but gone under (no active website at the moment), the Craftsman meter is a good choice.

.

I have two Flukes, a 77 and a 73 both bought from ebay, the 77 is an ex military that cost me £25 that has travelled the world and has had a really tough time but still works perfectly and I've had it 15 years or more, the 73 stays in my shed for shed stuff. I remember when I first saw Flukes back in the late seventies, I found that that the older Flukes go for reasonable money. I also have a clamp meter that stays with my machines, that again was second hand but was quite expensive, it does the usual AC/DC and continuity but I got it because it measures current up to 1000 amps AC. Unless they get pinched there is no doubt these will see me out and have been real value for money.
Never be without your Fluke.

[barnbiketom]

Can I see some more examples of DC amps testing on motorcycles??? other than starter draw which I can 'sense' the starter is bad?

[posplayr]

Can I see some more examples of DC amps testing on motorcycles??? other than starter draw which I can 'sense' the starter is bad?

Depending on meter resolution quiescent draw is useful when battery is being drawn down.
also measuring batt charging current vs total alternator current is interesting.
If you are going for LEDs then more interest.

[bwringer]

Can I see some more examples of DC amps testing on motorcycles??? other than starter draw which I can 'sense' the starter is bad?

Anything where you need to test while the bike is running.

Diagnose bad coils -- see how much current each coil is drawing with key on and at various RPM. Sometimes bad coils will actually work for a while, but they'll draw a lot of current, heat up, and then fail while the bike is running.

Overall "sanity check" -- does the current draw with the key on make sense? You can also pull the fuses and replace one at a time to narrow down an issue.

I was chasing a very tricky issue that turned out to be a broken ground wire deep in the harness. The instrument bulbs worked, but they were actually grounding through the turn signal filaments, and the turn signals were acting strange. Measuring the amperage draw verified that they weren't drawing full current, and watching the readout while wiggling this and that finally located the problem area.

I've used it to verify which wire on electric grip heaters was low heat and which was high heat. Could have done the same thing with the ohm meter, but then I would have had to take apart a connector.

Verify how much current an ignitor or electronic ignition is drawing when the bike is running. Again, if it's drawing more (or less) than it should as it warms up, that may be the source of an intermittent problem.

Check how many amps your farkles (USB outlet, heated grips, LED lights, etc.) are drawing.

[barnbiketom]

Anything where you need to test while the bike is running.

Diagnose bad coils -- see how much current each coil is drawing with key on and at various RPM. Sometimes bad coils will actually work for a while, but they'll draw a lot of current, heat up, and then fail while the bike is running.

Overall "sanity check" -- does the current draw with the key on make sense? You can also pull the fuses and replace one at a time to narrow down an issue.

I was chasing a very tricky issue that turned out to be a broken ground wire deep in the harness. The instrument bulbs worked, but they were actually grounding through the turn signal filaments, and the turn signals were acting strange. Measuring the amperage draw verified that they weren't drawing full current, and watching the readout while wiggling this and that finally located the problem area.

I've used it to verify which wire on electric grip heaters was low heat and which was high heat. Could have done the same thing with the ohm meter, but then I would have had to take apart a connector.

Verify how much current an ignitor or electronic ignition is drawing when the bike is running. Again, if it's drawing more (or less) than it should as it warms up, that may be the source of an intermittent problem.

Check how many amps your farkles (USB outlet, heated grips, LED lights, etc.) are drawing.

very good stuff.
I especially like the thoughts on battery drain, and being able to isolate circuits.
Also the AC side would be cool at home in the breaker box too...just to see if I'm pushing the envelope on certain branches!!!

[Brendan W]

I have an older non auto-range one of these http://www.ebay.de/itm/Digipol-Multi...-/311460858179
Had it 30 years. It doesn't have current or diode function and it's two hands operation but gets straight into tricky places and great for quick tests.
Never seen anybody else with one. They have an assembly shop a mile from here.

[barnbiketom]

I have an older non auto-range one of these http://www.ebay.de/itm/Digipol-Multi...-/311460858179
Had it 30 years. It doesn't have current or diode function and it's two hands operation but gets straight into tricky places and great for quick tests.
Never seen anybody else with one. They have an assembly shop a mile from here.

That's cool too. The last real meter I had was a Knight-Kit I made from a kit, but I lost it (misplaced) then after a year or so, found it on the ROOF where I'd been ohming CB cables to a tower. needless to say it no longer worked.

[barnbiketom]

Well, I have been actively monitoring fleabay for flukes and I am consistently loosing, even with a Sniper program, as most of the other bidders must be using one also lol...
87s working or not go for over 100 bucks, and even a 23 I bid on, not working , went for over 50!! I have researched lots on the flukes and non working ones usually need the rotary cleaned/lubed and or fuses replaced.
I even considered a NEW one, more of an automotive one rather 'electronic' and then another avenue is the 'overseas' ones made by FLUKE in china...http://www.ebay.com/itm/FLUKE-F101-Kit-Palm-sized-Digital-Multimeter-Meter-Smaller-Than-Fluke-17B-no-
Amp-/121679222862?hash=item1c54a5984e:gAsAAOSw~OdVf8VE
but I'm not going for those since they may be counterfeit or????


So for now I picked up a NEW SEARS cheepie.. 17 bucks and I'm kinda impressed. nice leads, nice probes and the low resistance range actually almost reads zero hahaha. .3 ohms is better than the 4 ohms all my crap HF meters read hahaha
still looking for that fluke hahah

[Chris]

This is fun and a trip down memory lane. I was an avionics guy working both the flight line and the bench from 1971 to 2002 and so used quite a few different meters over the years. Anyone else learn on a PSM-6 (pronounced Psss'em Six, of course. ) like this one?



These days I really don't need a good meter very often so I keep a semi-cheap Craftsman meter in the top of the tool chest and it's the one I grab for common automotive tasks like checking battery voltage and the one that gets handed to the kids when they need a meter.

More rarely used is a Simpson 467 (PSM-45) left over from my airplane fixer days.



I always liked the Simpson 260 family of meters (and analog meters in general which are much easier to use to find the peak when aligning a circuit) but they were just too fragile for anything but on the bench stuff. That bakelite case would break in heartbeat.


Like I said, a fun thread. Are we going to talk about smoking HP RF signal generators by inadvertently transmitting into them or the tricks a bored tech can get a Tektronix o'scope to do like Lissajous patterns?

(NOTE: these photos are of generic examples of the meters under discussion and are not pictures of any old gov't test equipment in my possession. These are not the droids you're looking for.)

[posplayr]

What is the last cal date on that PSM-6? make sure it is up to date next time you need to check out your A scope.


This is also a nice desk top unit and they go for about $50 on ebay.
FLUKE 8600A DIGITAL MULTIMETER 4 1/2 DIGIT 2 MOHM

[Chris]

What is the last cal date on that PSM-6? make sure it is up to date next time you need to check out your A scope.


This is also a nice desk top unit and they go for about $50 on ebay.
FLUKE 8600A DIGITAL MULTIMETER 4 1/2 DIGIT 2 MOHM

I never used the 8600 but I did use the 8040a which was the functional equivalent to the Simpson 467. What endeared both those meters to me is that they were true RMS meters which let me use them instead of the HP 410B VTVM:



The 410B was introduced in the early 50s I think and remained the standard at least into the 70s. It was a pretty good meter but I never liked it and thought the tube in the probe was kind of clunky even if you could mutter to yourself that happiness was a warm probe when you went to use it. The Simpson and fluke DMMs were true RMS meters and thanks to their signal conditioning circuits very easy to use although they didn't have the high freq capability the old 410 did. I imagine it's all changed now and the whole idea of bit and piece repair of LRUs has gone away. I was already seeing that before I left the aircraft maintenance world and thought the USAF techs would probably end up just black box swappers eventually.

As for me, I don't even dabble in electronics any more and only occasionally open a case. The last time I worked anything I was fixing video projectors for my school in Japan by taking the 8 or 9 we were getting ready to throw away and managed to scramble the good parts to make 4 good ones. Now i'm even retired from teaching.

[Nessism]

Using my Harbor Freight "automotive" multimeter ($40 jobbie) this weekend to measure stator resistance. Used the 200 ohms scale. Measurement shows .8 ohms, with the spec being between .7-.4. Question: is it asking too much to use this cheap meter to measure such a resistance? I know one thing: I don't have confidence in this thing so there is always that...

[jabcb]

Using my Harbor Freight "automotive" multimeter ($40 jobbie) this weekend to measure stator resistance. Used the 200 ohms scale. Measurement shows .8 ohms, with the spec being between .7-.4. Question: is it asking too much to use this cheap meter to measure such a resistance? I know one thing: I don't have confidence in this thing so there is always that...

Your multimeter has an internal resistance. Touch the leads together to determine the internal resistance. Its likely something like 0.2 to 0.4 ohms.

The resistance you measured is the combination of the stator resistance + the multimeter internal resistance.
So the stator resistance is about: 0.8 - 0.3 = 0.5 ohms

[Nessism]

Your multimeter has an internal resistance. Touch the leads together to determine the internal resistance. Its likely something like 0.2 to 0.4 ohms.

The resistance you measured is the combination of the stator resistance + the multimeter internal resistance.
So the stator resistance is about: 0.8 - 0.3 = 0.5 ohms

Checked and the meter is showing .1 ohms when the leads are touched together. I'm going to take the stator to work today and borrow a fluke to compare against.

[eil]

I wouldn't trust an el-cheapo meter to be super accurate in general. Especially on the lower 5% of the scale (under 10 ohms in this case). Although sometimes they'll surprise you...