Newbie Analog Multimeter?

   / Newbie Analog Multimeter? #1  

PSDStu

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I am trying to measure a wire to see if it has 10ohms resistance with a Analog Multimeter and I have a question.

My meter only has one Ohm range setting of (OHM x1k).

The meter face readings are 0-1-2-3-4-5-6-8-10-20-30-40-60-100-200-1K.

When I took my reading the meter stayed at 0.

If it read 10 on my scale would that be 10ohms.......or 10k ohms????

I'm a little confused....thanks!
 
   / Newbie Analog Multimeter? #2  
I am trying to measure a wire to see if it has 10ohms resistance with a Analog Multimeter and I have a question.

My meter only has one Ohm range setting of (OHM x1k).

The meter face readings are 0-1-2-3-4-5-6-8-10-20-30-40-60-100-200-1K.

When I took my reading the meter stayed at 0.

If it read 10 on my scale would that be 10ohms.......or 10k ohms????

I'm a little confused....thanks!

10 on your meter would be 10k Ohms. That's a pretty cheap meter and it is difficult to read very low resistances. Zero the meter very carefully with the leads shorted. You may see a very small change in the needle between leads shorted (connected together) and 10 Ohms. Sorry I can't help you more. Can you take the resistor to Radio Shack and have them use one of their better meters to check it. Or better yet buy a meter. Knowing how to use a multimeter can be a very valuable skill. Radio Shack probably has some books on the subject.
 
   / Newbie Analog Multimeter? #3  
digital meters are so cheap now. I threw all my analog's away years ago
 
   / Newbie Analog Multimeter? #4  
Stu, reading 10 ohms accurately is going to be a challenge with any meter. With a good VOM like a Simpson 260 with a 1X scale, zeroing the meter will be critical as well as having good batteries in the meter. The leads of whatever you are measuring will also have to be very clean to not induce some contact resistance that could be 1 or 2 ohms. That's a 10% to 20% error when you are measuring 10 ohms. If you have a critical need for exactly 10 ohms, comparing your item under test to a known standard would also be a helpful method. You can buy 1% precision resistors, but common resistors have tolerances of 5% to 20%. You can easily measure 100 ohms, but 10 ohms is a challenge. 1 ohm or less takes specialized equipment, often used in making meter shunts.
 
   / Newbie Analog Multimeter? #5  
As jinman said.. most consumer grade meters are terrible at measuring low value resistance.

if you need exact, do an in circuit test using a known value resistor and a power supply.. measure the voltage drop across your un known resistance wire.. that and the voltage drop avcross the know resistor will = the supply voltage.. then use ohms law to figure out the unknown resistor value.. e=IR

soundguy
 
   / Newbie Analog Multimeter?
  • Thread Starter
#6  
Stu, reading 10 ohms accurately is going to be a challenge with any meter. With a good VOM like a Simpson 260 with a 1X scale, zeroing the meter will be critical as well as having good batteries in the meter. The leads of whatever you are measuring will also have to be very clean to not induce some contact resistance that could be 1 or 2 ohms. That's a 10% to 20% error when you are measuring 10 ohms. If you have a critical need for exactly 10 ohms, comparing your item under test to a known standard would also be a helpful method. You can buy 1% precision resistors, but common resistors have tolerances of 5% to 20%. You can easily measure 100 ohms, but 10 ohms is a challenge. 1 ohm or less takes specialized equipment, often used in making meter shunts.

Thanks Jinman! I remember when I was in the Navy all the EM's and ET's had there trusty Simpson Meter with them and I would love to be able to get my hands on one. Trying to measure 10 ohms with the new Multimeters nowadays is proving difficult.

I am trying to troubleshoot a faulty Stepper Motor on a portable generator and one of things to test first is to disconnect the Stepper Motor wiring harness from the Idle Control Board and measure the ohms between the pins on the wiring harness. Any reading other than 10 ohms indicates a faulty Stepper Motor or harness.

I did find digital VOM with a 200 ohm scale and will try it to see what type of reading I get.

Thanks again,

Stu
 
   / Newbie Analog Multimeter? #7  
Thanks Jinman! I remember when I was in the Navy all the EM's and ET's had there trusty Simpson Meter with them and I would love to be able to get my hands on one. Trying to measure 10 ohms with the new Multimeters nowadays is proving difficult.

I am trying to troubleshoot a faulty Stepper Motor on a portable generator and one of things to test first is to disconnect the Stepper Motor wiring harness from the Idle Control Board and measure the ohms between the pins on the wiring harness. Any reading other than 10 ohms indicates a faulty Stepper Motor or harness.

I did find digital VOM with a 200 ohm scale and will try it to see what type of reading I get.

Thanks again,

Stu

Stu, use that 200 ohm scale to compare a questionable stepper to a known good one. If they read the same, you're good to go. Rarely do coils short out so that they change value by a few ohms. Most of the time you will see them be dead shorts or very low resistance or they will be completely open. The best thing you can do is test against a working motor if you have one available. Of course, I don't know the complete application or if a motor winding is what you are measuring. However, 10 ohms sounds like a typical resistance of a small motor's winding.
 
   / Newbie Analog Multimeter? #8  
measuring in circuit like that is going to be dicey.

my sugestion is to find a cheap analog vom with an rx1 scale ( rat schack used to have them.. etc. ).. then also buy a 10 ohm resistor in the highest tolerance they carry, use that as a 'reference' if you are lucky you can find a 5%.. and thus have a scale of 9.5-10.5 vs a 10% tolerance giving you a scale range of 9-11 ohms.

soundguy
 
   / Newbie Analog Multimeter? #9  
Stu, use that 200 ohm scale to compare a questionable stepper to a known good one. If they read the same, you're good to go. Rarely do coils short out so that they change value by a few ohms. Most of the time you will see them be dead shorts or very low resistance or they will be completely open. The best thing you can do is test against a working motor if you have one available. Of course, I don't know the complete application or if a motor winding is what you are measuring. However, 10 ohms sounds like a typical resistance of a small motor's winding.

ditto that. I was out on a job testing electric servo's for a tranny on a piece of heavy equipment.. in our setup, coil was about 10ohms.. the bad ones were either showing open.. or low range like 2.5.. etc. had an occasional one with a bad connectior show real high like 25.. but gives you a good idea to go with by compairing to a known good one.


soundguy
 
   / Newbie Analog Multimeter?
  • Thread Starter
#10  
Thanks Jim and Chris for the assistance!

Stu
 

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