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Multimeter


kurt

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I looked at all the Sperry clamp meters and this model is the only one on their website that shows a picture of a display where the measurement is down to 2 decimal points. (10 mA)

What will you use all that resolution for (0.010 A)?

Looking for minor current on water pipes or grounding conductors.

Why would I need a meter that reads 400, 600 or 1000 amps?

I wouldn't care so much about the actual value, but I want the meter to be more sensitive than the cheap one I bought.

That is exactly it!

The instruments you listed are designed to measure LOAD current.

What you want to measure is LEAKAGE current. It's doubtful that the load current meters are going to be much good for such small currents.

The scales are too large (even at 40A) and the accuracy is too low.

Remember, the highest accuracy is obtained the closer you get to full scale (in this case 40A).

What you want is a leakage tester. Fluke 360:

Click to Enlarge
tn_201222114118_360.jpg

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About $700.00

Fluke application note:

Download Attachment: icon_adobe.gif leakage current fluke.PDF

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OK, so you've got a measurement (albeit of questionable accuracy); what do you use for a cut point (problem leakage)?

Just curious.

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Lately, I suck at communicating.

Of course you don't need a 289 or an 88 for home inspecting. My point was, the things I use the meter for are simple and basic functions that almost any meter can accomplish.

As you suspected, the capabilities of my meters centered on my needs as a mechanic- measuring milliamps and graphing those readings over milliseconds was important to me. Now, not so much; I would never dream of re-purchasing my meters with my current job. well, maybe the 88, it's a workhorse.

I had other specialized stuff that could record 5 data streams simultaneously and superimpose the anomalies. The early ABS systems required those capabilities.

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Hi,

Back around 1997 while I was still a rookie and doing lots of extra things that most experienced inspectors wouldn't have dreamed of doing, I lost my wiggy someplace and for a short time used a really cheap multi-meter to verify power was on to stuff that wouldn't function for one reason or another, to test thermocouples, to test limit controls on furnaces, to identify faulty heating elements in electric furnaces, to test limit controls and thermostats on baseboard heaters, confirm bonding between hot and cold pipes when I couldn't see a bond, check voltage at disconnect switches, confirm breaker boxes weren't hot before I touched them and to test high limit cutoffs and thermostats at electric water heaters. I'd use the MM along with 100ft. extension cord to verify voltage delivered to receptacles and to check for proper polarity and grounding.

Then one day I set the switch in the wrong position and fried it when I'd checked a 240volt dryer receptacle. I got in my truck, went down to the nearest big orange box, bought a wiggy and then went back to the job and back to the basics. I purchased my first SureTest in 1999 while in Vegas at an ITA conference. While there, I talked to lots of folks about what they were doing and weren't doing and after that never saw the need to return to using a MM.

Don't get me wrong; they are a great tool, and very useful, for diagnostics. I just don't think our mandate is diagnostics beyond what we can do with a SureTest or something similar or a wiggy. I'm not even really certain that we need to be using clamp-on meters.

ONE TEAM - ONE FIGHT!!!

Mike

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...........to test thermocouples, to test limit controls on furnaces, to identify faulty heating elements in electric furnaces, to test limit controls and thermostats on baseboard heaters, confirm bonding between hot and cold pipes when I couldn't see a bond, check voltage at disconnect switches, confirm breaker boxes weren't hot before I touched them and to test high limit cutoffs and thermostats at electric water heaters.

ONE TEAM - ONE FIGHT!!!

Mike

That's the stuff I wish I had a very simple manual for; something with pictures and arrows. I could figure it out, sure.....I just don't want to. I'm loaded down figuring out some fancy house waterproofing details and things I'm good at....figuring out diagnostics with new tools just doesn't fit in the schedule now.

Kenney, thanks for the link to the $260 model.....that's more in line with what I was thinking.

For 99% of what I do, I have my Wiggy and my Suretest; I agree, that's about all we need. I've even got the old Suretest with the retractable grounding prong courtesy of Scott Warga.

But, it would be nice on occasion to do the other stuff and not stand there looking dumb.

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Pictures and manuals is easy.

When I was back in the army I'd subscribed to a bunch of book-of-the-month type deals from The Handyman Club of America, Time Life Home Improvement Library, Time Life Fix-it-Yourself Library, Fine Homebuilding and similar. That's where I learned to do that kind of stuff. When I was getting ready to retire from the Army and knew I was getting into this gig, but before I knew what the job actually entailed, I'd studied all of those and then went around my place in Colorado Springs and around the Provost Marshal's Office on Ft. Carson and began practicing how to test that stuff.

Go to the Library and borrow the T-L F-i-Y books on Lighting and Electricity, Home Heating and Cooling, Kitchen and Bathroom Plumbing, Household Electric Wiring by Kittle and Home Heating and Air Conditiong Systems by Kittle. Alternatively, I can send 'em to you in one of those "If it fits, it ships" boxes.

ONE TEAM - ONE FIGHT!!!

Mike

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I found this cheaper one, a product of Chinese slave labor of course. Aren't they all, though? It has the 0-4A range and takes 2 AA's.

http://www.dhgate.com/cm-05-leakage-cur ... 11b24.html

You do understand that this is a probe only. It requires a multimeter or scope to actually display measurements. Also lacks any voltage functions ('course if you need a scope or DMM to use you already have that).

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I found this cheaper one, a product of Chinese slave labor of course. Aren't they all, though? It has the 0-4A range and takes 2 AA's.

http://www.dhgate.com/cm-05-leakage-cur ... 11b24.html

You do understand that this is a probe only. It requires a multimeter or scope to actually display measurements. Also lacks any voltage functions ('course if you need a scope or DMM to use you already have that).

Thanks, Bob. I couldn't make out the tiny thumbnail.
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Just so's I'm clear in my thick head.....

The Amprobe AC50A is the full deal....clamp, DMM, etc., and the cheap chinese model in the thumbnail is the probe only.

Yes?

Yes! It is AC only, however. If you think you might need to measure DC (current or volts) (alarm system, any low voltage control circuits, etc.)

you will need to shell out more bucks for a more elaborate meter, or just buy a cheap DMM only. This device is intended for AC LEAKAGE current so it does not provide those features.

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Kurt,

Amprobe has a whole buffet of clamp meters - some of them are clamp/multimeters with dual displays, etc. You can check them out here:

http://www.amprobe.com/Amprobe/usen/Pro ... Meters.htm

We really should try and work out some kind of a deal with Amprobe and their owner, Fluke, 'cuz they're right here in our own back yard only twenty minutes away.

ONE TEAM - ONE FIGHT!!!

Mike

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Yeah, cool. How 'bout the ACD-14? about $150, dual display, temperature.

I've got my little cheapie Greenlee for DC current.

ACD 14 is discontinued! Manufacturers recall!

http://www.testequipmentdepot.com/ampro ... acd-14.htm

Yeah, but the replacement is a free ACD 14 Plus or a free ACD 14 TRMS Plus.

http://www.amprobe.com/Amprobe/usen/Ser ... Recall.htm

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