zs and r1+r2

[SPECIAL LOCATION]

the origin is from where you personally decide to originate from, in this case at the f/spur. normally at the incomer. In a large installation with many DB's the Ze would be taken at the supply(the distribution cct) to each of the DB's and not at the incomer. The f/spur has a supply which then feeds a final cct

Same Thing

quite so Mr T.

 

[Robojin]

Maximum zs for a 3 amp 1362 fuse is 13.12 @0.4s and 18.56 @5s.

GH are you not referring to the Amperage flow above for disconnection, as opposed to the ohms reading for Zs or am I being dopey ?:|

PS I don't see any disconnection time curves or Zs for 1362 in either OSG or BS7671 or I could just blind of course

 

[Andy™]

Ze is NOT external to the building.It is "External to the installation"

<snip>

i stand corrected

 

[green-hornet]

GH are you not referring to the Amperage flow above for disconnection, as opposed to the ohms reading for Zs or am I being dopey ?:| PS I don't see any disconnection time curves or Zs for 1362 in either OSG or BS7671 or I could just blind of course

Table 41.4 page 49 in the big red book

 

[SPECIAL LOCATION]

Table 41.4 page 49 in the big red book

Quite so GH...Guiness Drink

But I think you may have thrown a wobbler for Robojin by quoting the 80% rule of thumb figures..

which maybe why didn't immediately spot it in the Big Red Un!

Maximum zs for a 3 amp 1362 fuse is 13.12 @0.4s and 18.56 @5s.

i.e. 0.4s dis

Table 41.2 3A BS1362 Max Zs=16.4ohm 80%=13.12ohm

and 5s dis

Table 41.4 3A BS1362 Max Zs=23.2ohm 80%=18.56ohm

Just thought I would add that point in case any college type bods are trying to spot your numbers in the tables pages 48/49.

bit of team work never when amiss. :x

 

[Robojin]

Yup Special it did throw me for a second or two as I forgot the BRB quotes 100% ohms Law

BTW I've been working on a calculator for all this in excel, I've nearly finished for T&E just a few things to tidy up such as r1+r1 expected ohms results, finnishing the CaCgCiCc calcs etc, and will likely add SWA and possibly singles, is this of interest to anyone?

 

[Apache]

Yup Special it did throw me for a second or two as I forgot the BRB quotes 100% ohms LawBTW I've been working on a calculator for all this in excel, I've nearly finished for T&E just a few things to tidy up such as r1+r1 expected ohms results, finnishing the CaCgCiCc calcs etc, and will likely add SWA and possibly singles, is this of interest to anyone?

not really

 

[Robojin]

not really

:coat

Well I could add gestation tables for Bovidae if that helps you Patch ; \

 

[Apache]

:coat Well I could add gestation tables for Bovidae if that helps you Patch ; \

pah 280d

 

[Apache]

Yup Special it did throw me for a second or two as I forgot the BRB quotes 100% ohms LawBTW I've been working on a calculator for all this in excel, I've nearly finished for T&E just a few things to tidy up such as r1+r1 expected ohms results, finnishing the CaCgCiCc calcs etc, and will likely add SWA and possibly singles, is this of interest to anyone?

Can you compress it as a zip file? You can attach those to the posts using the paperclip

 

[SPECIAL LOCATION]

Yup Special it did throw me for a second or two as I forgot the BRB quotes 100% ohms LawBTW I've been working on a calculator for all this in excel, I've nearly finished for T&E just a few things to tidy up such as r1+r1 expected ohms results, finnishing the CaCgCiCc calcs etc, and will likely add SWA and possibly singles, is this of interest to anyone?

Your obviously thinking along the lines of a good electrician then IMHO..

I already have various Excel calc pages for doing these sort of bits..

R1+R2's lengths, MCB ratings volt drops, current or power drawn etc.. etc..

I assume some people will have them built into the computerised certificate software they use? ?:|

 

[Andy™]

BTW I've been working on a calculator for all this in excel, I've nearly finished for T&E just a few things to tidy up such as r1+r1 expected ohms results, finnishing the CaCgCiCc calcs etc, and will likely add SWA and possibly singles, is this of interest to anyone?

should be useful. attach it to a thread in tips/tricks?

 

[Robojin]

should be useful. attach it to a thread in tips/tricks?

I'm looking to see how easy it would be to convert to a web page (get my Son with his BSc in computer science to do this), and then possibly link via the tips & tricks section for the leccys to access due to the stuff covered

As to your encouragement

Andy, Special If I can send a screen dump I'd appreciate your opinions

Patch

 

[Apache]

I'm looking to see how easy it would be to convert to a web page (get my Son with his BSc in computer science to do this), and then possibly link via the tips & tricks section for the leccys to access due to the stuff coveredAs to your encouragement

Andy, Special If I can send a screen dump I'd appreciate your opinions

Patch

to you too

 

[Nicky Tesla]

yes and the Zdb is to all intents and purposes the Ze for that board

 

[Nicky Tesla]

yes and the Zdb is to all intents and purposes the Ze for that board

woops looks like i missed a few pages there.

thanks for the comment earlier spesh

 

[SPECIAL LOCATION]

woops looks like i missed a few pages there.thanks for the comment earlier spesh

:^O :^O:^O:^O:^O

easy done!

answer post....

then find there were two more pages you hadn't read!Blushing:_| :^O :^O:^O

 

[sivoodoo]

I am very interested in your calculator Robojin.

Lets see it!

Regards

 

[a1]

I am very interested in your calculator Robojin.Lets see it!

Regards

Me too.

Have you got an ETA for it to go on the "Tips and Tricks" forum?

Don't put it or anything related to it (Including Screnshots/dumps) on an open forum like this one.

Tips and Tricks is only open to sparks and student sparks who can prove their status and have been registered on here for a while with a limited amount of useful posts.

 

[ianmacd]

Tips and Tricks is only open to sparks and student sparks who can prove their status and have been registered on here for a while with a limited amount of useful posts.

My posts are of a limited useful amount. Does that count