#Eureka - or - understanding Zs/Ze/R1+R2

[Desiderata]

Not sure if I post in here or elsewhere (no access to the trainee section as yet, just waiting for details to be confirmed and access granted).

But I had a eureka moment at around 2:30am this morning, woke up and completely understood the relationship between Zs, Ze, R1+R2, why we do R1+R2/4 to get expected reading at each socket, why we don't use Rn and how they relate to the circuit protection tables for maximum Zs allowable - all seems very simple but it's brilliant to actually be able to say to myself I completely understand the whole thing at last!

I was also thinking about two way switching at the same time - I really need to get a life and sleep and have normal dreams methinks!

 

[Wilko]

Happy days !
Now you'll have to give up drinking so you won't forget ... just kidding

 

[Pete999]

Not sure if I post in here or elsewhere (no access to the trainee section as yet, just waiting for details to be confirmed and access granted).

But I had a eureka moment at around 2:30am this morning, woke up and completely understood the relationship between Zs, Ze, R1+R2, why we do R1+R2/4 to get expected reading at each socket, why we don't use Rn and how they relate to the circuit protection tables for maximum Zs allowable - all seems very simple but it's brilliant to actually be able to say to myself I completely understand the whole thing at last!

I was also thinking about two way switching at the same time - I really need to get a life and sleep and have normal dreams methinks!

You are testing Zs earthloop so why would you want Rn, as for 2 way not much to it really, if you are stumped PM me

 

[Desiderata]

You are testing Zs earthloop so why would you want Rn, as for 2 way not much to it really, if you are stumped PM me

Exactly - you don't need Rn - but I've put it all together as to why we don't need it in my head so I feel like i really understand now, rather than the typical initial student response of "Um yeah, not sure why" )

Thank's for the pm offer - I'll no doubt take you up on that soon enough !

 

[Desiderata]

Happy days !
Now you'll have to give up drinking so you won't forget ... just kidding

Maybe that's where I'm going wrong, I rarely drink, perhaps a whisky and coffee before bed

 

[telectrix]

"a" whisky, as in 1 bottle?

 

[Desiderata]

"a" whisky, as in 1 bottle?

Good god man, I'm a lightweight at drinking, one bottle and I could kiss the work i'm doing goodbye for at least two weeks !

 

[westward10]

Good god man, I'm a lightweight at drinking, one bottle and I could kiss the work i'm doing goodbye for at least two weeks !

I work better.

 

[telectrix]

Winston Churchill was 2 bottles a day minimum, and he lived to 90.

 

[7029 dave]

Not sure if I post in here or elsewhere (no access to the trainee section as yet, just waiting for details to be confirmed and access granted).

But I had a eureka moment at around 2:30am this morning, woke up and completely understood the relationship between Zs, Ze, R1+R2, why we do R1+R2/4 to get expected reading at each socket, why we don't use Rn and how they relate to the circuit protection tables for maximum Zs allowable - all seems very simple but it's brilliant to actually be able to say to myself I completely understand the whole thing at last!

I was also thinking about two way switching at the same time - I really need to get a life and sleep and have normal dreams methinks!

I take it you are in the trade.? If you are dreaming about the job that tells me you are liking it.?

 

[sparksburnout]

I work better.

Good man. Get it down you.

 

[DPG]

It's always a satisfying feeling when you have been trying to get you rhead round something and then the penny finally drops. Nice one! Daz

 

[Desiderata]

I take it you are in the trade.? If you are dreaming about the job that tells me you are liking it.?

Well I didn't feel like I was having a nightmare, so yes I damn well am enjoying, I must be to be working for free in return for gaining experience!

 

[Midwest]

But I had a eureka moment at around 2:30am this morning, woke up and completely understood the relationship between Zs, Ze, R1+R2, why we do R1+R2/4 to get expected reading at each socket, why we don't use Rn and how they relate to the circuit protection tables for maximum Zs allowable - all seems very simple but it's brilliant to actually be able to say to myself I completely understand the whole thing at last!

I was also thinking about two way switching at the same time - I really need to get a life and sleep and have normal dreams methinks!

The Royal College of Psychiatrists, could base a whole conference on that. Have a couple of whiskies tonight, you might dream of something more risqué

 

[sparksburnout]

The Royal College of Psychiatrists, could base a whole conference on that. Have a couple of whiskies tonight, you might dream of something more risqué

Iv'e had some bloody odd dreams, mostly after overindulgence, but I can honestly say NONE of them have involved electrical measurements. I think you might need professional help your mind is obviously disturbed......

 

[Risteard]

perhaps a whisky and coffee before bed

I would recommend whiskey rather than whisky. (I can explain the difference if you are unsure.) You can then mix this with your coffee and have an Irish Coffee if you like.