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1) Verify anything that a 3-light tester says.

2) Verify anything that a volt stick tells you.

3) Test the operation of heat pump & electric furnace elements.

4) Use it to check for current on water pipes & ground rods.

5) Use it to check the amp draw of air conditioner and heat pump compressors.

Do *not* use it to check phantom voltage. For that you'll need a Wiggy.

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I have a relatively inexpensive clamp meter that I bought to measure current, (so I can be just like Jim. [:)] ) But I don't use it much, if ever.

One restriction I have here is that I'm not permitted to "perform work" inside a breaker panel without an electrician's license. So we must be careful where we stick our meter probes, eh?

One example of where I would like to take a voltage measurement in the breaker panel, but can't, is in a small multi-unit residence with underground service and no access to the meter cabinet.

The only way then to determine if the service is 3-phase or single phase would be to take a measurement between the two hot conductors somewhere in the apartment. If one of the major appliances is missing, great, I can measure the voltage there.

In Canada, 3-phase service means 120/208 volts for the residence. This is only significant info to some worrywart types, so I just report it as a possibility and move on in most cases.

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To use the Eico vacuum tube voltmeter (VTVM) to check a circuit, simply plug it in and wait a couple of minutes. If the tubes warm up, the circuit is good. [:)]

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That's funny. Those are all good ideas. My problem is I'm at the check battery stage, and would like to do it to test amp draw, elements, and that sort of stuff.

I'm also at the age of being minimally interested in figuring it out and just want something to walk me thru it with a better manual that speaks to me more than the lame stuff currently supplied with the gear.

I need a multimeter for HI work instruction manual.

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Kurt,

If my scanner would talk to my new computer, I'd scan some stuff for you that shows you how to use one for this gig. Alas, my computer refuses to communicate with my perfectly good 12 year old scanner that's only made about 50 scans total and I can't find a driver for the damned thing. I've been planning to go see what those things cost these days so I might have something for you in a day or so.

ONE TEAM - ONE FIGHT!!!

Mike

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Kurt,

If my scanner would talk to my new computer, I'd scan some stuff for you that shows you how to use one for this gig. Alas, my computer refuses to communicate with my perfectly good 12 year old scanner that's only made about 50 scans total and I can't find a driver for the damned thing. I've been planning to go see what those things cost these days so I might have something for you in a day or so.

ONE TEAM - ONE FIGHT!!!

Mike

Mike, I remember when Windows XP came out, it took me a couple of years to find a driver for my flat bed scanner.

We use fax a lot to send and receive booking sheets and info, so I took a chance and bought a new multifunction machine, Samsung SCX, in 2008 and it is still performing well. In scan, copy, or fax mode, you can feed multiple sheets into it. The top hinges up so you can scan a book the old way. You can scan to a HD or to a flash drive. It was about $200. Cartridges are $75.

It has its own brain, so you don't need a driver. In fact, I keep mine in the other office, and plug a laptop into it if I can't use a flash drive.

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That's funny. Those are all good ideas. My problem is I'm at the check battery stage, and would like to do it to test amp draw, elements, and that sort of stuff.

I'm also at the age of being minimally interested in figuring it out and just want something to walk me thru it with a better manual that speaks to me more than the lame stuff currently supplied with the gear.

I need a multimeter for HI work instruction manual.

Post a picture of your multimeter.

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I've got the basic DM-20. I'm not opposed to getting something nicer if it is beneficial to have something nicer.

DM-20

It doesn't have a clamp, so you can't use it to measure amperage (not practically, anyway). It'll only be useful for voltage.

I think you'd get more use out of a combination multi-meter, clamp-on meter. It doesn't have to be expensive. Look at the UEI D49 or the Sperry DSA 400.

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Kurt,

If my scanner would talk to my new computer, I'd scan some stuff for you that shows you how to use one for this gig. Alas, my computer refuses to communicate with my perfectly good 12 year old scanner that's only made about 50 scans total and I can't find a driver for the damned thing. I've been planning to go see what those things cost these days so I might have something for you in a day or so.

ONE TEAM - ONE FIGHT!!!

What kind of scanner is it?

Mike

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I've got the basic DM-20. I'm not opposed to getting something nicer if it is beneficial to have something nicer.

DM-20

It doesn't have a clamp, so you can't use it to measure amperage (not practically, anyway). It'll only be useful for voltage.

I think you'd get more use out of a combination multi-meter, clamp-on meter. It doesn't have to be expensive. Look at the UEI D49 or the Sperry DSA 400.

But don't waste your money on too cheap of a clamp meter. Mine only measures current down to 0.0 Amps. That is pretty useless.

My 1950's vacuum tube meter is good for aligning radios. And it is fun. Here, I'm measuring the current draw of the big meter, which is only about 0.01 amps, still enough to stop your heart, but my meter reads 00.0 [:(]

When I put a big 1500 watt load on the cord, we get a reading of 6 amps. OK the meter works. Notice how the voltage has been pulled down to 109 vac, by the heater.

You want a clamp meter that reads milliamps. In the third pic, there could be current flowing thru the pipes. We still don't know for sure.

Also the wires need to be separated to read amperage. You can't measure amps in a multistrand cord with a clamp meter, unless they're all carrying current from the same source. If one strand is hot and the other is neutral, the clamp reads 00.0.

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The truth is that I don't use a volt meter on the job much. I've a Fluke 336 clamp meter for checking ground rods like Jim said and to find the 208 V leg on some 3 phase unbalanced neutral residential services but that's it.

I just bought an inspector III that Douglas recommended a while back. Great instrument. It's more useful to me than any voltmeter, but still too big to carry around in my pouch. I keep it and the clamp meter handy in a tool bag in the kitchen.

Marc

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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)

http://www.sperryinstruments.com/product/dsa500a

$60 seems like a fair price, too.

I like this one, but it uses those little button batteries that go dead pretty fast I think.

http://www.valuetesters.com/Amprobe-ACD ... r-600A.php

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With the single exception of looking for minor current on water pipes, I can't imagine a situation where a home inspector would need to be able to measure milliamps. And even that exception is pushing it.

If you're going to use it on the job it'll be for testing the operation of heating elements in water heaters, amp draw at compressors, operation of electric furnace/heat pump elements, and for more in-depth testing of receptacles than you can do with a three-light tester. That's all pretty crude work.

You don't need anything more precise than a tenth of an amp and you don't need true RMS. Any of the baseline meters from the major manufacturers will be fine. I started using a lot of UEI equipment because they were headquartered here and I could stop in for free repairs that were done while I watched. After a while, I just got to really like them.

Sperry & GB are fine. It's hard to go wrong with Fluke. Like point & shoot cameras, it doesn't really make a whole lot of difference.

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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.

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There was a time when I used a multimeter daily, so I still have a Fluke 289, an 88 and a bunch of accessories. I recently lost my SureTest so I broke out my Fluke and it's now my daily driver on inspections. It's a little more cumbersome than the SureTest but it's paid for and I trust it without reservation.

I use the inductive amp clamp and the thermometer the most, but I also use it for testing polarity, grounds and anytime the three light tester reports something funky.

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