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#41
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Is Coax-Digital Usually High Voltage !@!#??
Pooh Bear wrote:
Class II ( double insulated ) equipment is still allowed to have a significant (1mA ) leakage current though. And if you have a home cinema system with half a dozen boxes connected together, you can get 5 legal milliamps, which is starting to get dangerous. I measured mine yesterday. 50v and 0.4mA. It was more when I had a different TV and I can't even feel the tingle now. -- Eiron No good deed ever goes unpunished. |
#42
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Is Coax-Digital Usually High Voltage !@!#??
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#43
Posted to rec.audio.tech
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Is Coax-Digital Usually High Voltage !@!#??
"Don Pearce" wrote in message ... Amps kill, not volts. Else we'd all be dead many times over from static discharges. The old canard again! You have never had an electrostic shock then? The body has a resistance. To get current to flow through that resistance you need volts (Ohms law applies here as it does everywhere). If the source resistance of the electricity is too great to let much current flow, you won't get the volts. Simple really. Maybe, if you were talking about a permanently connected circuit. It's what happens at the instant the person touches the voltage that causes the shock. If the shock continues indefinitelty, there is indeed a fault condition! If you have the volts, you will have the amps. If you have enough *source impedance* you will NOT have many amps, regardless of open circuit voltage. Simple really. If you have the source resistance, you don't get the volts. You can't read any better than your knowledge of electric shock then. Simple really. Yes, you seem to be. MrT. |
#44
Posted to rec.audio.tech
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Is Coax-Digital Usually High Voltage !@!#??
"Matt Ion" wrote in message news:Ga6mg.69138$Mn5.52303@pd7tw3no... The simpler way to look at it is: a certain amount of current will stop the heart, and given a certain amount of resistance in the path through the body, the higher the voltage, the more current will flow - simple Ohm's law. At least Ohm knew it was the TOTAL resistance, including source impedance, that limits the current flow. However source impedance does NOT change the open circuit voltage. Just like E=MC^2, many people seem to know ohms law, but not how to use it. MrT. |
#45
Posted to rec.audio.tech
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Is Coax-Digital Usually High Voltage !@!#??
On Wed, 21 Jun 2006 17:53:48 +1000, "Mr.T" MrT@home wrote:
If you have the source resistance, you don't get the volts. You can't read any better than your knowledge of electric shock then. Do you know what a potential divider is? It is a chain of two resistors, the lower one grounded. The voltage at the junction is the voltage at the top, multiplied by the lower resistance, and divided by the sum of the two resistances. The lower resistance would be the body, and the upper the source resistance. The body has quite a low resistance compared to the source resistance of the static. That is why you don't get the volts - they are lost in the potential divider. That doesn't go for all static of course. Some comes from quite a low resistance, so you do get the volts - and hence also the current. But since static charge is generally held on quite low capacitances, there isn't a lot of charge there, so the current is very brief. That is why for some static belts they are easily felt, but still undamaging. What you don't want is that high voltage, low source resistance and plenty of reserve of charge. That is what will kill you. Simple really. Yes, you seem to be. MrT. Now do you get it? d -- Pearce Consulting http://www.pearce.uk.com |
#46
Posted to rec.audio.tech
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Is Coax-Digital Usually High Voltage !@!#??
On Wed, 21 Jun 2006 17:59:58 +1000, "Mr.T" MrT@home wrote:
"Matt Ion" wrote in message news:Ga6mg.69138$Mn5.52303@pd7tw3no... The simpler way to look at it is: a certain amount of current will stop the heart, and given a certain amount of resistance in the path through the body, the higher the voltage, the more current will flow - simple Ohm's law. At least Ohm knew it was the TOTAL resistance, including source impedance, that limits the current flow. However source impedance does NOT change the open circuit voltage. Just like E=MC^2, many people seem to know ohms law, but not how to use it. MrT. Why are you so hung up on the open circuit voltage? You can't touch it - all you can ever get is the pd across YOU. That depends on the source resistance - and of course your resistance. You claim to know Ohms law, and I'm sure you do - so for goodness sake use it. d -- Pearce Consulting http://www.pearce.uk.com |
#47
Posted to rec.audio.tech
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Is Coax-Digital Usually High Voltage !@!#??
"Don Pearce" wrote in message ... Why are you so hung up on the open circuit voltage? You can't touch it - all you can ever get is the pd across YOU. Er yes, that's how you get the tingle. What on earth are you smoking? That depends on the source resistance - and of course your resistance. As I stated all along, Thanks for now agreeing. You claim to know Ohms law, and I'm sure you do - so for goodness sake use it. OK, please tell me exactly how to calculate the amount of tingle a person will feel, using only ohms law. So far you keep claiming a person should feel NO shock at all, when that is demonstrably NOT the case. But hang on, in another post you admitted a person *may* feel a non fatal shock, but now seem to claim it can't be so according to ohms law. Which is it? It seems you are just trying to muddy the water so as not to appear too contradictory. MrT. |
#48
Posted to rec.audio.tech
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Is Coax-Digital Usually High Voltage !@!#??
On Thu, 22 Jun 2006 17:18:15 +1000, "Mr.T" MrT@home wrote:
"Don Pearce" wrote in message ... Why are you so hung up on the open circuit voltage? You can't touch it - all you can ever get is the pd across YOU. Er yes, that's how you get the tingle. What on earth are you smoking? Pronoun without a referent - that is really helpful in understanding what you are talking about. That depends on the source resistance - and of course your resistance. As I stated all along, Thanks for now agreeing. Actually, as I've stated all along. If you have been arguing, I would have to ask why. You claim to know Ohms law, and I'm sure you do - so for goodness sake use it. OK, please tell me exactly how to calculate the amount of tingle a person will feel, using only ohms law. Use their body resistance, source resistance, emf, all the usual stuff. So far you keep claiming a person should feel NO shock at all, when that is demonstrably NOT the case. Never claimed any such thing. But hang on, in another post you admitted a person *may* feel a non fatal shock, but now seem to claim it can't be so according to ohms law. Which is it? Whose posts are you reading? They certainly aren't mine. It seems you are just trying to muddy the water so as not to appear too contradictory. MrT. My position has remained unchanged throughout. d -- Pearce Consulting http://www.pearce.uk.com |
#49
Posted to rec.audio.tech
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Is Coax-Digital Usually High Voltage !@!#??
"Don Pearce" wrote in message ... Do you know what a potential divider is? It is a chain of two resistors, the lower one grounded. The voltage at the junction is the voltage at the top, multiplied by the lower resistance, and divided by the sum of the two resistances. Thanks for the high school physics lesson, but you really need to study a lot further than that. The lower resistance would be the body, and the upper the source resistance. The body has quite a low resistance compared to the source resistance of the static. That is why you don't get the volts - they are lost in the potential divider. So just to make it clear, are you actually agreeing with me that you can still get a shock, or claiming that because the *continuous* volts are low, that no shock is possible? That doesn't go for all static of course. Some comes from quite a low resistance, so you do get the volts - and hence also the current. But since static charge is generally held on quite low capacitances, there isn't a lot of charge there, so the current is very brief. That is why for some static belts they are easily felt, but still undamaging. Well there's your problem, read what is written, and don't assume instantaneous is the same as continuous, or that resistance is the same as impedance, and all will be well. What you don't want is that high voltage, low source resistance and plenty of reserve of charge. That is what will kill you. Where did I ever say otherwise? MrT. |
#50
Posted to rec.audio.tech
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Is Coax-Digital Usually High Voltage !@!#??
On Thu, 22 Jun 2006 17:29:18 +1000, "Mr.T" MrT@home wrote:
"Don Pearce" wrote in message ... Do you know what a potential divider is? It is a chain of two resistors, the lower one grounded. The voltage at the junction is the voltage at the top, multiplied by the lower resistance, and divided by the sum of the two resistances. Thanks for the high school physics lesson, but you really need to study a lot further than that. The lower resistance would be the body, and the upper the source resistance. The body has quite a low resistance compared to the source resistance of the static. That is why you don't get the volts - they are lost in the potential divider. So just to make it clear, are you actually agreeing with me that you can still get a shock, or claiming that because the *continuous* volts are low, that no shock is possible? I've never said otherwise - you are pushing against an open door here. That doesn't go for all static of course. Some comes from quite a low resistance, so you do get the volts - and hence also the current. But since static charge is generally held on quite low capacitances, there isn't a lot of charge there, so the current is very brief. That is why for some static belts they are easily felt, but still undamaging. Well there's your problem, read what is written, and don't assume instantaneous is the same as continuous, or that resistance is the same as impedance, and all will be well. I have no problem. What I wrote above is no different to anything I have written. What you don't want is that high voltage, low source resistance and plenty of reserve of charge. That is what will kill you. Where did I ever say otherwise? Nowhere. I've just added that. d -- Pearce Consulting http://www.pearce.uk.com |
#51
Posted to rec.audio.tech
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Is Coax-Digital Usually High Voltage !@!#??
"Don Pearce" wrote in message ... I have no problem. What I wrote above is no different to anything I have written. So what is it you actually disagree with then? MrT. |
#52
Posted to rec.audio.tech
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Is Coax-Digital Usually High Voltage !@!#??
On Thu, 22 Jun 2006 19:27:23 +1000, "Mr.T" MrT@home wrote:
"Don Pearce" wrote in message ... I have no problem. What I wrote above is no different to anything I have written. So what is it you actually disagree with then? MrT. Looking back over the thread, I came in to correct those who said "the volts don't matter, just the amps". I pointed out that the amps are caused directly by the volts, through ohm's law - so yes, the volts do matter. At that point you joined in, accusing me of ranting. That ****ed me off - ranting is not my style. You have spent the rest of the thread to date telling me stuff I know, and accusing me of saying something different. I don't understand what it is you are trying to achieve. d -- Pearce Consulting http://www.pearce.uk.com |
#53
Posted to rec.audio.tech
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Is Coax-Digital Usually High Voltage !@!#??
"Don Pearce" wrote in message ... Looking back over the thread, I came in to correct those who said "the volts don't matter, just the amps". I pointed out that the amps are caused directly by the volts, through ohm's law - so yes, the volts do matter. But I never said they didn't matter. However people have lived after touching 220kv power lines too. I don't think I want to get into that though. At that point you joined in, accusing me of ranting. That ****ed me off - ranting is not my style. You have spent the rest of the thread to date telling me stuff I know, and accusing me of saying something different. I don't understand what it is you are trying to achieve. Are you sure you have that the right way around! Lets see, this appears to be my first reply. ------------------------------------------------ "Don Pearce" wrote in message ... Amps kill, not volts. Else we'd all be dead many times over from static discharges. The old canard again! You have never had an electrostic shock then? The body has a resistance. To get current to flow through that resistance you need volts (Ohms law applies here as it does everywhere). If the source resistance of the electricity is too great to let much current flow, you won't get the volts. Simple really. Maybe, if you were talking about a permanently connected circuit. It's what happens at the instant the person touches the voltage that causes the shock. If the shock continues indefinitely, there is indeed a fault condition! If you have the volts, you will have the amps. If you have enough *source impedance* you will NOT have many amps, regardless of open circuit voltage. Simple really. ----------------------------------------------------------------------- |
#54
Posted to rec.audio.tech
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Is Coax-Digital Usually High Voltage !@!#??
On Thu, 22 Jun 2006 20:06:33 +1000, "Mr.T" MrT@home wrote:
"Don Pearce" wrote in message ... Looking back over the thread, I came in to correct those who said "the volts don't matter, just the amps". I pointed out that the amps are caused directly by the volts, through ohm's law - so yes, the volts do matter. But I never said they didn't matter. However people have lived after touching 220kv power lines too. I don't think I want to get into that though. At that point you joined in, accusing me of ranting. That ****ed me off - ranting is not my style. You have spent the rest of the thread to date telling me stuff I know, and accusing me of saying something different. I don't understand what it is you are trying to achieve. Are you sure you have that the right way around! Lets see, this appears to be my first reply. ------------------------------------------------ "Don Pearce" wrote in message ... Amps kill, not volts. Else we'd all be dead many times over from static discharges. The old canard again! You have never had an electrostic shock then? The body has a resistance. To get current to flow through that resistance you need volts (Ohms law applies here as it does everywhere). If the source resistance of the electricity is too great to let much current flow, you won't get the volts. Simple really. Maybe, if you were talking about a permanently connected circuit. It's what happens at the instant the person touches the voltage that causes the shock. If the shock continues indefinitely, there is indeed a fault condition! Are you saying that Ohms law takes a while to get going? I don't understand what point you are making here. If you have the volts, you will have the amps. If you have enough *source impedance* you will NOT have many amps, regardless of open circuit voltage. Listen carefully - volts "across the body" - the only volts that count. It doesn't matter a fig what the open circuit volts are. ( as I've pointed out to you elsewhere; you seem to be fixated on it). d -- Pearce Consulting http://www.pearce.uk.com |
#55
Posted to rec.audio.tech
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Is Coax-Digital Usually High Voltage !@!#??
"Don Pearce" wrote in message ... Are you saying that Ohms law takes a while to get going? I don't understand what point you are making here. FFS we were talking about small electric shocks. Now **** off unless you want to provide the ohms law formula for calculating the exact degree of shock felt by a person from an unknown voltage with an unknown source impedance. You have already admitted a person CAN get a tingle/shock from a non faulty device and not die, so there is nothing left to debate! MrT. |
#56
Posted to rec.audio.tech
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Is Coax-Digital Usually High Voltage !@!#??
On Thu, 22 Jun 2006 23:45:02 +1000, "Mr.T" MrT@home wrote:
"Don Pearce" wrote in message ... Are you saying that Ohms law takes a while to get going? I don't understand what point you are making here. FFS we were talking about small electric shocks. Now **** off unless you want to provide the ohms law formula for calculating the exact degree of shock felt by a person from an unknown voltage with an unknown source impedance. You are going to have to explain what you are talking about much more clearly. How do you propose to equate a physiological impression to a voltage via an ohms law formula? I am aware of only one Ohms law, and it contains just volts amps and ohms - there is no physiology in there. And of course, this would be much better without the swearing. You have already admitted a person CAN get a tingle/shock from a non faulty device and not die, so there is nothing left to debate! Why would I need to "admit" such a thing? I've known it all my life - I first found it out at the age of four when I tried to light a sparkler in the heater bar of an electric fire. d -- Pearce Consulting http://www.pearce.uk.com |
#57
Posted to rec.audio.tech
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Is Coax-Digital Usually High Voltage !@!#??
"Don Pearce" wrote in message ... Why would I need to "admit" such a thing? I've known it all my life - Good, we are in agreement then, so now **** off if you are not just a troll. MrT. |
#58
Posted to rec.audio.tech
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Is Coax-Digital Usually High Voltage !@!#??
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#59
Posted to rec.audio.tech
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Is Coax-Digital Usually High Voltage !@!#??
"GregS" wrote in message ... You don't need a formula, you need a meter. Ah, but you must have missed all the times Don said to use ohms law. MrT. |
#60
Posted to rec.audio.tech
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Is Coax-Digital Usually High Voltage !@!#??
On Fri, 23 Jun 2006 15:51:54 +1000, "Mr.T" MrT@home wrote:
"GregS" wrote in message ... You don't need a formula, you need a meter. Ah, but you must have missed all the times Don said to use ohms law. MrT. You mean the bit where I wrote: "You are going to have to explain what you are talking about much more clearly. How do you propose to equate a physiological impression to a voltage via an ohms law formula? I am aware of only one Ohms law, and it contains just volts amps and ohms - there is no physiology in there." You really are a something of a fool, aren't you, Mr T? d -- Pearce Consulting http://www.pearce.uk.com |
#61
Posted to rec.audio.tech
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Is Coax-Digital Usually High Voltage !@!#??
"Don Pearce" wrote in message ... You mean the bit where I wrote: "You are going to have to explain what you are talking about much more clearly. How do you propose to equate a physiological impression to a voltage via an ohms law formula? I am aware of only one Ohms law, and it contains just volts amps and ohms - there is no physiology in there." No that came much later. You were the one who suggested using ohms law, and *I* was the one who asked you how to apply it in this case. Google is your friend if your memory is failing. MrT. |
#62
Posted to rec.audio.tech
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Is Coax-Digital Usually High Voltage !@!#??
On Fri, 23 Jun 2006 16:26:30 +1000, "Mr.T" MrT@home wrote:
"Don Pearce" wrote in message ... You mean the bit where I wrote: "You are going to have to explain what you are talking about much more clearly. How do you propose to equate a physiological impression to a voltage via an ohms law formula? I am aware of only one Ohms law, and it contains just volts amps and ohms - there is no physiology in there." No that came much later. You were the one who suggested using ohms law, and *I* was the one who asked you how to apply it in this case. Google is your friend if your memory is failing. MrT. My friend, my memory is far better than yours. I said you could use Ohms law to find the current. It was you who demanded I tell you how to use it to measure the physiological impression. d -- Pearce Consulting http://www.pearce.uk.com |
#63
Posted to rec.audio.tech
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Is Coax-Digital Usually High Voltage !@!#??
"Don Pearce" wrote in message ... My friend, my memory is far better than yours. I said you could use Ohms law to find the current. It was you who demanded I tell you how to use it to measure the physiological impression. Since that is what we were discussing, this is a pretty **** weak attempt at saving face. Anyhow since you have now agreed with my original assertion, there is not much to be gained by dragging it on any further. MrT. |
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