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Spark, I've got some bad news for you buddy. You're DEAD! Not only that, you've been dead for quite some time if the Fluke can't see some R across you. But before we start calling your next of kin, is there any chance that you have your meter on "diode check", instead of "ohms" or inadvertantly gotten into a manual, low resistance range? For now, let's stipulate that you are among the living. I haven't checked out Winnie's link yet but let's consider why it doesn't seem too credible. A modern DMM will usually have an imput impedance of about 10 million ohms. You would probably be hard pressed to find one with less than a million ohms. This is a good thing because we wish to measure a circuit without influencing it. To consider the possibility of a DMM being a shock hazzard, we have to think of it as a 9 volt power supply with a source impedance of 10 million ohms. Our unknown voltage is Vdead (Vd). Our poor victim's resistance is Rdead( Rd),(maybe we should use URdead). Total resistance (Rt)= Rsource (Rs) + Rdead (Rd). We can use voltage divider equations to note that Vt/Vd = Rt/Rd. If you happened to look like 100,000 ohms of resistance, you would plug & chug & come up with 9/Vd = 10,100,000/100,000. Vd = 0.089 volts in this case. Your current is 8.9^-7 A. So my gut feeling is that the only way that a DMM set to R is going to kill someone, is if Jet Li is using it.
Why don't you try taking a 9 volt battery and putting yourself in series with your Fluke on DC uA across it. Then if you can get a hold of a Simpson 260 or other analog meter that has its input R expressed in thousands of ohms per volt(R depends on voltage scale that you use), try this. Measure your battery voltage with the analog volt meter and your DMM. Now put a 1M resistor in series with the battery and measure between the other terminal and the free end of the resistor. Quite a difference between the 2 readings now, right? That's because, "All the world's a voltage divider." Joe
[This message has been edited by JoeTestingEngr (edited 12-24-2005).]
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Entire Thread
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Transformers: mind-boggling, mysterious beasts
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Spark Master Flash
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12/21/05 06:54 PM
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Re: Transformers: mind-boggling, mysterious beasts
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ghost307
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12/21/05 07:06 PM
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Re: Transformers: mind-boggling, mysterious beasts
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BobH
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12/21/05 07:53 PM
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Re: Transformers: mind-boggling, mysterious beasts
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jwhite
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12/21/05 07:53 PM
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Re: Transformers: mind-boggling, mysterious beasts
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Spark Master Flash
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12/21/05 08:06 PM
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Re: Transformers: mind-boggling, mysterious beasts
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jwhite
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12/21/05 08:53 PM
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Re: Transformers: mind-boggling, mysterious beasts
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Spark Master Flash
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12/21/05 11:08 PM
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Re: Transformers: mind-boggling, mysterious beasts
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Spock
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12/21/05 11:41 PM
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Re: Transformers: mind-boggling, mysterious beasts
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Spark Master Flash
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12/22/05 12:12 AM
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Re: Transformers: mind-boggling, mysterious beasts
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jwhite
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12/22/05 12:26 AM
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Re: Transformers: mind-boggling, mysterious beasts
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JoeTestingEngr
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12/22/05 12:44 AM
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Re: Transformers: mind-boggling, mysterious beasts
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jwhite
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12/22/05 01:37 AM
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Re: Transformers: mind-boggling, mysterious beasts
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Admin
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12/22/05 03:52 AM
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Re: Transformers: mind-boggling, mysterious beasts
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RODALCO
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12/22/05 04:58 AM
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Re: Transformers: mind-boggling, mysterious beasts
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Larry Fine
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12/22/05 05:11 AM
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Re: Transformers: mind-boggling, mysterious beasts
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Spark Master Flash
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12/22/05 05:13 AM
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Re: Transformers: mind-boggling, mysterious beasts
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Spark Master Flash
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12/22/05 05:18 AM
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Re: Transformers: mind-boggling, mysterious beasts
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Admin
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12/22/05 05:50 AM
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Re: Transformers: mind-boggling, mysterious beasts
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Spark Master Flash
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12/22/05 10:49 AM
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Re: Transformers: mind-boggling, mysterious beasts
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winnie
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12/22/05 01:26 PM
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Re: Transformers: mind-boggling, mysterious beasts
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WFO
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12/22/05 02:30 PM
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Re: Transformers: mind-boggling, mysterious beasts
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RODALCO
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12/23/05 08:01 AM
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Re: Transformers: mind-boggling, mysterious beasts
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Spark Master Flash
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12/23/05 04:10 PM
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Re: Transformers: mind-boggling, mysterious beasts
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SolarPowered
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12/23/05 05:18 PM
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Re: Transformers: mind-boggling, mysterious beasts
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WFO
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12/23/05 07:11 PM
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Re: Transformers: mind-boggling, mysterious beasts
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Spark Master Flash
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12/23/05 07:44 PM
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Re: Transformers: mind-boggling, mysterious beasts
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WFO
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12/24/05 12:08 AM
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Re: Transformers: mind-boggling, mysterious beasts
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Spark Master Flash
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12/24/05 12:47 AM
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Re: Transformers: mind-boggling, mysterious beasts
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winnie
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12/24/05 02:29 AM
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Re: Transformers: mind-boggling, mysterious beasts
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Scott35
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12/24/05 02:40 AM
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Re: Transformers: mind-boggling, mysterious beasts
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Scott35
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12/24/05 02:48 AM
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Re: Transformers: mind-boggling, mysterious beasts
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WFO
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12/24/05 03:11 AM
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Re: Transformers: mind-boggling, mysterious beasts
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Spark Master Flash
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12/24/05 03:24 AM
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Re: Transformers: mind-boggling, mysterious beasts
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JoeTestingEngr
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12/24/05 04:06 AM
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Re: Transformers: mind-boggling, mysterious beasts
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Larry Fine
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12/24/05 04:20 AM
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Re: Transformers: mind-boggling, mysterious beasts
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JoeTestingEngr
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12/24/05 05:48 AM
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Re: Transformers: mind-boggling, mysterious beasts
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Trumpy
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12/24/05 10:11 AM
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Re: Transformers: mind-boggling, mysterious beasts
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winnie
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12/24/05 01:13 PM
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Re: Transformers: mind-boggling, mysterious beasts
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Spark Master Flash
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12/24/05 03:31 PM
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Re: Transformers: mind-boggling, mysterious beasts
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iwire
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12/24/05 03:48 PM
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Re: Transformers: mind-boggling, mysterious beasts
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JoeTestingEngr
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12/24/05 05:09 PM
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Re: Transformers: mind-boggling, mysterious beasts
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JoeTestingEngr
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12/24/05 05:10 PM
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Re: Transformers: mind-boggling, mysterious beasts
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JoeTestingEngr
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12/24/05 06:26 PM
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Re: Transformers: mind-boggling, mysterious beasts
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Spark Master Flash
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12/24/05 06:46 PM
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Re: Transformers: mind-boggling, mysterious beasts
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JoeTestingEngr
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12/24/05 07:31 PM
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Re: Transformers: mind-boggling, mysterious beasts
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Dnkldorf
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12/24/05 08:51 PM
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Re: Transformers: mind-boggling, mysterious beasts
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Spark Master Flash
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12/25/05 12:15 AM
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Re: Transformers: mind-boggling, mysterious beasts
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Spark Master Flash
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12/25/05 12:30 AM
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Re: Transformers: mind-boggling, mysterious beasts
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Spark Master Flash
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12/25/05 12:32 AM
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Re: Transformers: mind-boggling, mysterious beasts
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WFO
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12/25/05 12:35 AM
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Re: Transformers: mind-boggling, mysterious beasts
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Spark Master Flash
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12/25/05 03:09 AM
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Re: Transformers: mind-boggling, mysterious beasts
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JoeTestingEngr
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12/25/05 04:54 AM
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Posts: 28
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