Electric shock treatment

[tim west]

So you measure Potential difference with a Galvanometer do you?

You can do, if you use it to measure the current passing through a known series resistance.

They may be called voltmeters, but moving coil instruments are just sensitive galvanometers with a switchable selection of series resistances built into the case.

but they are more than just galvanometers then hence an added resistance to gather the PD information.
DVM's tend to use the resistance in an R/C network to control either a microcontroller or an oscillator the pulse train from this is counted and the time function gives the vakue of the voltage measured the display is configured to make sense of this value into the voltage reading we see, with a bit of simple circuitry it is quite easy to get other functions such as frequency reading etc, hence why a lot of DVM's are multi functional.

 

[ban-all-sheds]

I must admit to being somewhat surprised by a few of the posts in this topic particularly from BAS ... Is this the same BAS who used to post with authority a year or so ago?

No - with even more authority now...

Voltage Potential in circuit terms is the ability of one element of a design to induce a voltage in another ... the higher the potential the more likely it is to occur. This has absolutely nothing to do with voltage or potential difference or anything else of similar vein nor does it suggest a potential difference between the circuits.

I have no problem with any of that, and I already knew that is a very real issue for circuit and equipment designers to have to deal with.

Why is this causing everyone such a problem?

To find the answer to that I suggest you go back and re-read all of Tim West's posts, and see if you think he's been describing the potential for Component A to induce a voltage within Component B, or the potential for a voltage to come into existence between Component A and Component B.....

 

[tim west]

Bas think of two wirewound components sitting close to each other, resemble something in the big electrical world?

Ooh - how about a transformer?

Much valued for safety reasons because they separate things - there is no potential difference between the primary and the secondary.

but still a hazard to board designers who dont want induced voltages affecting different parts of their circuitry.

 

[ban-all-sheds]

but they are more than just galvanometers then hence an added resistance to gather the PD information.

Ah - but if all I have is a galvanometer, and I want to measure PD, and I get an appropriate external resistor and connect it in series with my galvanometer between the two points where I want to measure PD, have I still not got a galvanometer?

...hence why a lot of DVM's are multi functional.

As are analogue multimeters with moving coil galvanometers at their heart..

But I'm just having some light-hearted fun now - best not to continue this as a serious topic....

 

[Softus]

deleted

Too late.

...you are taking softus's lead here...

Not so - ban-all-sheds was the first to point out the error in bernardgreen's post, which is where the discussion about PD started.

you may interpret my thoughts as anything else than that then you are mistaken and misquoting me.

How could that possibly happen, when your posts are so correct, clear and unambiguous?

 

[tim west]

but they are more than just galvanometers then hence an added resistance to gather the PD information.

Ah - but if all I have is a galvanometer, and I want to measure PD, and I get an appropriate external resistor and connect it in series with my galvanometer between the two points where I want to measure PD, have I still not got a galvanometer?

no as you've created a VM now, same as a complex circuit can be made out of simple components, on their own they are just that components but put them together and all of a sudden you could have a radio.

 

[DESL]

Good God

From someone getting a shock from a sink to re invemting the 'Laws of Physics' I find this thread very entertaining.

Even to the point of considering digging my 35yr old college notes out to make sure I didn't miss something.

To quote a song "Captain you canna change the law of physics"

 

[Good God]

Good God

What do you want? I was just watching Dragons' Den.

 

[Jim2287]

lol u made whole new account so u could say that .... nordski

 

[tim west]

How could that possibly happen, when your posts are so correct, clear and unambiguous?

why thank you softus for finally agreeing with that, knew you come around in the end

 

[megawatt]

BAS Wrote:

To find the answer to that I suggest you go back and re-read all of Tim West's posts, and see if you think he's been describing the potential for Component A to induce a voltage within Component B, or the potential for a voltage to come into existence between Component A and Component B.....

I thought the first case which I agreed with ... Now I'm not sure as this topic has become so damn convoluted

Time to withdraw I think

MW

 

[tim west]

it works in both cases but in different ways,
the first case consists of two coil components and Bas correctly stated its basically a transformer so induced voltages are created.

the second case is more akin to tuned circuits where an aerial and receiver are created and unwanted signals are transmitted and received and can interfere with sensitive layouts, this is where the shielded sections of pcb's come into play.

As sparks we all know about the need for shielded cables in certain applications.