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Jack_in_VA
Premium Member
join:2007-11-26
North, VA

Jack_in_VA to Msradell

Premium Member

to Msradell

Re: [Electrical] Re: Electrical problem

said by Msradell:

Jack, I've always respected and agreed with your opinions on here until this case. Infinite ohms corresponds to an extremely high level, 0 ohms mean there aren't any, 2 very different points on the scale!! If you touch your probe to 2 ends of a wire you will read 0 ohms, if you hold the 2 probes in the air you will get infinite number of ohms which is what you should have if you major between the elements of a water heater and ground.

You are right because that is the conventional way to describe it. I'm just saying that an infinite number is the same as no or zero ohms.

It's conventional terminology that has been around forever and was very necessary when analog ohmmeters needed by be "zeroed" by touching the probes together and turning the pot to make the meter needle match the zero mark on the scale. That "zero" operation is necessary with an analog ohmmeter for measurement accuracy.

SparkChaser
Premium Member
join:2000-06-06
Downingtown, PA

SparkChaser

Premium Member

said by Jack_in_VA:

It's conventional terminology that has been around forever and was very necessary when analog ohmmeters needed by be "zeroed" by touching the probes together and turning the pot to make the meter needle match the zero mark on the scale. That "zero" operation is necessary with an analog ohmmeter for measurement accuracy.

Yes, that's ZERO ohms. Probes not touching is infinite ohms.

cowboyro
Premium Member
join:2000-10-11
CT

cowboyro to Jack_in_VA

Premium Member

to Jack_in_VA
said by Jack_in_VA:

It's conventional terminology that has been around forever and was very necessary when analog ohmmeters needed by be "zeroed" by touching the probes together and turning the pot to make the meter needle match the zero mark on the scale. That "zero" operation is necessary with an analog ohmmeter for measurement accuracy.

The terminology has never been around.
Zero-ing an analog ohmmeter insures that a zero resistance (short-circuit) registers as 0 and not 0.7 or beyond the 0 an the analog scale.
An open circuit registers as infinity. The scale of the analog meter shows infinity with an open circuit.

robbin
Mod
join:2000-09-21
Leander, TX

robbin to Jack_in_VA

Mod

to Jack_in_VA
said by Jack_in_VA:

I'm just saying that an infinite number is the same as no or zero ohms.

Infinity equals zero (not)

UHF
All static, all day, Forever
MVM
join:2002-05-24

UHF to Jack_in_VA

MVM

to Jack_in_VA
Ok, I think I see what you mean, and where the confusion is coming in. An open circuit reads "zero" (no deflection) on the scale, because the analog scale on ohms reads "backwards", where zero is full deflection and an open, or infinite ohms, reads as no deflection on the scale, just like zero volts would.
85281231 (banned)
join:2014-02-01

85281231 (banned)

Member

Have not used an analog meter in a long time but I remember the Ohms scale having an infinite symbol(sideways 8) when the needle is at rest and zero on the other extreme, two completely different things.

OhmsLaw
@suddenlink.net

OhmsLaw to Jack_in_VA

Anon

to Jack_in_VA
said by Jack_in_VA:

said by Msradell:

Jack, I've always respected and agreed with your opinions on here until this case. Infinite ohms corresponds to an extremely high level, 0 ohms mean there aren't any, 2 very different points on the scale!! If you touch your probe to 2 ends of a wire you will read 0 ohms, if you hold the 2 probes in the air you will get infinite number of ohms which is what you should have if you major between the elements of a water heater and ground.

You are right because that is the conventional way to describe it. I'm just saying that an infinite number is the same as no or zero ohms.

It's conventional terminology that has been around forever and was very necessary when analog ohmmeters needed by be "zeroed" by touching the probes together and turning the pot to make the meter needle match the zero mark on the scale. That "zero" operation is necessary with an analog ohmmeter for measurement accuracy.

Jack, you are TOTALLY and COMPLETELY wrong on this one. When you "zero" a meter, you are adjusting it to read a DEAD SHORT as a DEAD SHORT (because a reading of, say 20 Ohms could lead you down the wrong path if you're checking for shorts in a motor winding). How do you do the zero process? By SHORTING the leads together, thereby creating a ZERO OHMS condition.

I know you think that if you yell at other people enough that it will prove you are right, but this time your are most certainly wrong. Period.

Get out your meter and measure the resistance of a short piece of wire.