# Digital meter or how to read it



## Madman (Jan 5, 2008)

I had been talking about voltage, current, and such, in another topic on smoke units. Along the many replies, we got to talking about voltage and current. Well, now that I have received my $.01 meter, I'd like to learn alittle more about how to use it. Here is a photo of it's face. Pretty isn't it? I have already figured out the AC/DC voltage portions. They are the two white bands on the upper portion. But what can I do with all of the other stuff?


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## Dwight Ennis (Jan 2, 2008)

By putting the meter in series with something, you can read the current that something draws during operation. To place the meter in series, disconnect one wire from the something and connect that wire to the meter lead. Connect the other meter lead to the place on the something that the original wire connected to. 

You can check "continuity" of something - connect the meter and set it to read resistance. See if it reads something or shows no resistance. Check several ranges because something may have a high-resistance connection.


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## steam5 (Jun 22, 2008)

I use my meter to mostly measure volts, current, and resistance. I also use the continuity tester. 

As you have found volts already I'll give you a couple of words on the other functions to get you started. 

Current (A): to measure current the meter must be in series with the circuit being measured. This is good for measuring motor current draw. 

Resistance (ohm): To measure resistance put the meter across the circuit to be measured. In the simplest case I check resistor values for dropping voltage to head lights. 

Continuity tester: This is the red section at the 6 o clock position on your meter. If you touch the probes of the meter together you should get a noise. I use this to test if circuits are broken or to make sure I haven't bridged two together. Useful to make sure the motor is isolated from the track in a DCC install or to test a fuse. NOTE, for the noise to come on you need a low resistance path. Some small short circuits enough to short a DCC system will not set of the noise. So some times its best to use the resistance section to confirm the result. 

There are other functions on your meter, but the above are the ones you will use most. If you understand basically what is happening electrically and what you want to measurer, using one is intuitive. Every modeler should have one.


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## Mike Reilley (Jan 2, 2008)

*SPECIFICATIONS
*- The meter is handheld Digital Multimeter for measuring DC and AC Voltage, DC Current, Resistance, Diode and Transistor with battery operated.
- Display: Blue Backlight LCD, 1999 counts, updates 2-3/sec
- Measuring method: Dual-slope integration A/D Converter
- Operating Environment: 0 to 40 °C
- Storage Temperature: -10°C to 50°C
- Power: 9V Battery, NEDA 1604 or 6F22 Type
- Fuse Protection: 200mA/250V
- Size: 138mm x 69mm x 31mm
- Weight: Approx. 160g 

*DC VOLTAGE*
- Measurement Range 200mV-600V 
*-* ±0.5% of rdg ± 2 digits
- Overload Protection: 250V rms

*AC VOLTAGE*
- Measurement Range 200V-600V
- ±1.2% ± 10 digits
- Overload Protection: 600VDC or rms
*
DC CURRENT*
- Measurement Range DC 200uA-10A
*-* ±1% of rdg ± 2 digits
- Overload Protection: F 200mA/250V fuse (10A range unfused)

*RESISTANCE* 
- Measurement Range 200 Ohms - 2M Ohms
*-* ±0.8% of rdg ± 3 digits
- Maximum Open Circuit Volatge: 3.2V
- Overload Protection: 250VDC or rms

*DIODE
- *Show the approx. forward voltage drop of the Diode

*TRANSISTOR
*- Measurement Range hFE TEST (0-1000)


Manual for sale


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## Mike Reilley (Jan 2, 2008)

Things you can do"

a. Measure AC and DC voltages...put the probes across the thing you want to measure...put the switch in the white areas
b. Measure current...put the probes in series with the current you want to measure...to make it flow through the unit...put the switch on the amperage part...2 to 5 o'clock ... AND put the probes into the left most hole and the center hole. If you do this wrong, you will get magic smoke out of the device and it will no longer work. Be sure NOT to put more than 10 Amps through it either...you get more than magic smoke when you do that.

c. Measure resistance...put the probes across the two leads of a resistive device...put switch on the resistance part...6 to 9 o'clock 

d. Test transistors...plug them into the PNP or NPN socket...you can test diodes too.


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## Greg Elmassian (Jan 3, 2008)

Be careful when measuring current, notice the "normal" connections to the meter go to ma, i.e. milliamperes... 

When you measure amps, you need to move the probe wire to the other socket. 

Be REAL careful when you are measuring current, that you have it right, since all the current goes through the meter. 

The analogies are, voltage is like water pressure, you have a big pipe, and you tap a little hole into it and put in a pressure meter. 

Measuring current, you have to measure the ENTIRE flow in the pipe, so all the "water" (current) would have to go through your meter. You can imagine making a mistake here is of much greater consequence. 

By the way, make sure you return the meter to the proper setting when measuring the voltage again, basically when measuring current, the meter is a dead short. Left in that mode and trying to measure a voltage will blow a fuse somewhere.. 

Greg


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## dbodnar (Jan 2, 2008)

Hi, Dan - I did a workshop for the local train club a few years back. It focused on how to use one of the $3.00 Harbor Freight meters to test various things on a garden railroad. The meter is different but the information will apply to your meter, too.

Have a look here:

Meter Notes


Let me know if you have any questions.

dave


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## John J (Dec 29, 2007)

Most meters have fuses inside them. So if the curent exceeds the rating the fuse blows and the meter is protected. Some of the fuses are accesable through the battery compartment. 

Then on the other hand some meters come all the way apart and have no battery compartment. If you got this used I would change the battery ASAP. That way you know your mearusments are correct.


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## Madman (Jan 5, 2008)

Thank you to all







. It's too late tonight







to practice but I will put all of your information to good use tomorrow


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## Mike Reilley (Jan 2, 2008)

Posted By dbodnar on 22 Nov 2010 02:52 AM 
Hi, Dan - I did a workshop for the local train club a few years back. It focused on how to use one of the $3.00 Harbor Freight meters to test various things on a garden railroad. The meter is different but the information will apply to your meter, too.

Have a look here:

Meter Notes


Let me know if you have any questions.

dave 


Dave, 

Your Meter Notes....are fantastic!!!!


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## John J (Dec 29, 2007)

Go to Radio Shack and get a couple of packages of the multi colored jumper wires with alligator clips on the ends. They will come in handy making connections to do current readings or monitoring voltages 

That way you can put it in a gondola or on a flat car between your battery car and your engine.


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## dbodnar (Jan 2, 2008)

Posted By Mike Reilley on 22 Nov 2010 10:58 PM 
Posted By dbodnar on 22 Nov 2010 02:52 AM 
Hi, Dan - I did a workshop for the local train club a few years back. It focused on how to use one of the $3.00 Harbor Freight meters to test various things on a garden railroad. The meter is different but the information will apply to your meter, too.

Have a look here:

Meter Notes


Let me know if you have any questions.

dave 


Dave, 

Your Meter Notes....are fantastic!!!! 
Thanks, Mike - the workshop went well so I must have gotten something right - it is amazing what you can do with a simple meter. I have seen them on special at Harbor Freight for as little as $1.99!

dave


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## RimfireJim (Mar 25, 2009)

- it is amazing what you can do with a simple meter. 
How true. I'd be lost without a meter. 

I have seen them on special at Harbor Freight for as little as $1.99! 
Or even less: HF had a coupon for a free meter this fall. 

The HF meters aren't great - they're slow in responding and I've had the dial detent feature fail on one of them, but they are plenty adequate for large scale train stuff and kicking around in a tool box. I normally use a Fluke I picked up at a swap meet (the continuity beeper is a nice feature), but have a couple of the HF ones around, too. A variety of test clips of different styles is well worth the money to complete the package.


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## Spule 4 (Jan 2, 2008)

Dave's notes are great (there are some good ones online, but this is the best toy train specific one I have seen) and JJ's suggestion is a good one too, while one can solder up their own leads too (I have done that) but you find they cost more than buying pre-made ones from Asia. 

Also Greg's point too about ensuring the right settings for voltage and current, I have cooked a couple meters accidentally in my time. And when you get into the high voltages and currents, there have been a few fatalities too with these things. 

Another tip: digital meters are best for absolute values, analog (needle) ones are best for sweep or span of readings. My days of troubleshooting Mercedes Benz climate control systems required both, some spans like resistance of temp sensors.


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## Madman (Jan 5, 2008)

Posted By Madman on 21 Nov 2010 08:54 PM 
I had been talking about voltage, current, and such, in another topic on smoke units. Along the many replies, we got to talking about voltage and current. Well, now that I have received my $.01 meter, I'd like to learn alittle more about how to use it. Here is a photo of it's face. Pretty isn't it? I have already figured out the AC/DC voltage portions. They are the two white bands on the upper portion. But what can I do with all of the other stuff? 












I want to be able to read the amount of amperage my house is using. I think I know how to use this meter to do that, but before I blow it up, can anyone, and I know who you are, tell me how to use this meter to read amperage?


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## Semper Vaporo (Jan 2, 2008)

Basically, with THAT meter you CAN NOT measure the current your house is drawing. You'd need 3 meters and some math to do that... your house has 3 wires in (in the U.S. anyway) and the current is shared amongst the three in rather complicated ways.

Besides the meter has a 10 amp upper range and your house is probably drawing more than that, especially at the moments when a big motor turns on, like your furnace or fridge.

It could be used to measure the current to individual components as long as they are not 3-wire (like the stove or clothes dryer.

The meter has to be in line with the circuit to be measured, unlike where you are measureing voltage where the meter is in parallel with the circuit. To measure current, cut one wire in two and connect one end to one meter lead and the other side of the cut wire to the other meter lead, then put the meter leads in the appropriate sockets of the meter and set the dial to the highest Amperage scale. Then apply power to the circuit and see what it measures. If the current exceeds the meter capability, you will probably have to replace the fuse in the meter. If the reading is well below the lower end of the scale it is set to then you can shut off the power and change the scale on the meter and then turn the circuit back on and measure it again. 

NOT FOR THE FAINT OF HEART (or_ untrained_[/b] novice) WHEN USING HOUSE POWER!


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## Madman (Jan 5, 2008)

I sort of expected that, thanks.


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## Mike Reilley (Jan 2, 2008)

http://cgi.ebay.com/New-9200-Triple...094?pt=LH_DefaultDomain_0&hash=item3c9b9d490e
To measure the current going into the house you need a clamp on current meter. To use it, you must take the faceplate off your breaker box and locate the big wires (little finger size) that come into the box from the street. There are three. One is red, one is white, one is black. Half of your house is powered off the black wire. Half is powered off the red wire. The white wire is the common return. The black and red wire typically go into the master breaker. To use the clamp on current meter, you simply put the clamp around the red wire, record the amperage....then repeat that on the black wire. THIS IS VERY DANGEROUS...AND IF YOU'RE NOT COMFORTABLE AROUND HIGH VOLTAGES, DON'T DO THIS. If you touch anything with your hands or the tool, you could get electrocuted...in fact, you're likely to get electrocuted.


Clamp on current meter


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## Torby (Jan 2, 2008)

In my case? With glasses on.


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## rdamurphy (Jan 3, 2008)

So.... Where does one get a $.01 meter? 

Thanks! Robert


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## bob7094 (Jan 3, 2008)

Posted By rdamurphy on 15 Jan 2011 01:32 PM 
So.... Where does one get a $.01 meter? 

Thanks! Robert A cent a meter? There's 2.54 of those to an inch!

-- Bob Mills


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## John J (Dec 29, 2007)

Remember in these hard times There is one source of tool bargins besides HF and such

Have you wandered around your local PAWN SHOP?

Here in the Phonenix I saw a three piece Snap On Tool Rool around with all the tools in it for 300 bucks.

lIt was well used but still had a lot of life left in it. 

JJ


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## rdamurphy (Jan 3, 2008)

Posted By bob7094 on 15 Jan 2011 06:41 PM 
Posted By rdamurphy on 15 Jan 2011 01:32 PM 
So.... Where does one get a $.01 meter? 

Thanks! Robert A cent a meter? There's 2.54 of those to an inch!

-- Bob Mills 



LOL!









Good point about Pawn Shops - and don't forget Craigslist...

Robert


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## Semper Vaporo (Jan 2, 2008)

Posted By John J on 15 Jan 2011 11:34 PM 
Remember in these hard times There is one source of tool bargins besides HF and such

Have you wandered around your local PAWN SHOP?

Here in the Phonenix I saw a three piece Snap On Tool Rool around with all the tools in it for 300 bucks.

lIt was well used but still had a lot of life left in it. 

JJ 


Another place is a 'second hand' store. Often these places have a sign that reads, "Antiques" but the only real antiques they have are the people that work there. Any object that is truly an antique, like you see being worth bazillions of bucko's on "Antiques Roadshow" will have been siphoned out of inventory by the owners long before the store opened that morning. So what they really have is just estate stuff that the deceased's family had no use for and so sold to the store to get it out of their hair.

Many years ago, I needed a woodworkers "Plane" for a cabinet project I was working on. I remembered the old Stanley plane my Dad had and figured I'd go to the hardware store to get one. All I found were an el-cheap-o folded piece of tinfoil with a single edge razor blade wedged in the bottom that I might have been able to afford and one that must have been made of platinum with solid gold accents and a titanium blade that only Bill Gates or Warren Buffet could afford.

Disillusioned, I went home and tried to figure out how I would repair the cabinet using my Swiss Army Knife. I couldn't.

Then, since I had copious free time on my hands because the cabinet project was on hold, I just went for a drive and on a whim went into an "Antique Shoppe". When I left the springs on my car were showing the effect of the weight of the 2 Stanley planes, 3 hand saws (Townsend and Stanley), 2 hammers (Sears), 8 screwdrivers (Craftsman), 10 wrenches (Craftsman), vise/anvil, hunk of RR rail used as an anvil, a handfull of various woodworking and metal-working files (Nicholson), a box of twist drills, a brace and a few bits, an Electric Sabre Saw and a box of blades for it, and two boxes of miscellaneous "wonders" (as in, "I wonder what those are for?") all for about the price of the folded tinfoil plane at the hardware store.

Oh dear... I probably should work on that cabinet someday.


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## Madman (Jan 5, 2008)

Posted By bob7094 on 15 Jan 2011 06:41 PM 
Posted By rdamurphy on 15 Jan 2011 01:32 PM 
So.... Where does one get a $.01 meter? 

Thanks! Robert A cent a meter? There's 2.54 of those to an inch!

-- Bob Mills 



*Check out Ebay
*


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