Microsoft excel formula for the adiabatic equation?

[spud1]

Does anyone know the Microsoft Excel 2010 formula entry to achieve the adiabatic equation?

Where, for example cell A1 is the prospective fault current, cell A2 is the disconnection time, cell A3 is the k factor and cell A5 is the resultant minimum c.p.c size?

Thanks

Spud

 

[D Skelton]

Does anyone know the Microsoft Excel 2010 formula entry to achieve the adiabatic equation?

Where, for example cell A1 is the prospective fault current, cell A2 is the disconnection time, cell A3 is the k factor and cell A5 is the resultant minimum c.p.c size?

Thanks

Spud

Put this formula in A5:

=SQRT(A1*A1*A2)/A3

 

[telectrix]

Put this equation in A5:

=SQRT(A1*A1*A2)/A3

that's beyond my limited computer skills. need a dummies guide. any offfers. never done excel before.

 

[D Skelton]

Im sure there would be plenty of online guides to the basics should you ever want to learn tel. It aint that hard, it's all entirely logical.

 

[spud1]

Brilliant thanks Mr Skelton!

 

[telectrix]

Im sure there would be plenty of online guides to the basics should you ever want to learn tel. It aint that hard, it's all entirely logical.

i'll have a try, but think i'll be brown bread before i've sussed it. took me a fortnight to learn how to copy and paste without gumming up the keyboard with solvite.

 

[wozz]

is this for a c&g project?

 

[UNG]

For those with an android mobile try this app

https://play.google.com/store/apps/details?id=com.procerts.adiabatic



Or for those with those i things it's more expensive

https://itunes.apple.com/gb/app/the-adiabatic-equation/id505845690?mt=8

but it costs 69p

 

[Geordie Spark]

Im sure there would be plenty of online guides to the basics should you ever want to learn tel. It aint that hard, it's all entirely logical.

... and therein lies the problem ....

 

[Knobhead]

Put this formula in A5:

=SQRT(A1*A1*A2)/A3

You forgot two sets of brackets.

I've used excel for so long I struggle to write conventional formula.

=SQRT(((A1*A1)*A2)/A3)

 

[Richard Burns]

You forgot two sets of brackets.

I've used excel for so long I struggle to write conventional formula.

=SQRT(((A1*A1)*A2)/A3)

I tried all the combinations and I already had one additional set fo brackets and found that the answer works each time correctly.
I think Excel is applying Bodmas correctly.
I used =SQRT((A1^2*A2)/A3)

 

[HandySparks]

I tried all the combinations and I already had one additional set fo brackets and found that the answer works each time correctly.
I think Excel is applying Bodmas correctly.
I used =SQRT((A1^2*A2)/A3)

Unless I'm misreading BGB 543.1.3, don't you take the square root of I²t before dividing by k, not after?

 

[Knobhead]

Sorry no

 

[telectrix]

For those with an android mobile try this app

https://play.google.com/store/apps/details?id=com.procerts.adiabatic



Or for those with those i things it's more expensive

https://itunes.apple.com/gb/app/the-adiabatic-equation/id505845690?mt=8

but it costs 69p

just downloaded the free app. brilliant. who needs excel?

 

[D Skelton]

You forgot two sets of brackets.

I've used excel for so long I struggle to write conventional formula.

=SQRT(((A1*A1)*A2)/A3)

It doesn't need them, it applies bodmas correctly.

Also, (A1*A1)*A2 is exactly the same as A1*A1*A2.

 

[Richard Burns]

I must admit I have now tried the various brackets and got it wrong each time so I do not know what I was doing before.
Last time it worked but this time when I re opened the spreadsheet it was the same as D Skelton's version and the various brackets did not work.
Must have been asleep (or am asleep now):dozey:

 

[Knobhead]

I'm too set in my ways.

It makes deconstructing formula easier. For complex formula I tend to use hidden cells to calculate small sections then put them together.

Its how I’ve worked for 35 years. I started on Lotus 123, that was a bitch. Before that it was a spreadsheet, a 10' long roll of paper.

 

[D Skelton]

For complex formula I tend to use hidden cells to calculate small sections then put them together.

Me too, for complex formula this definitely works. It makes calculations easier to tweak this way!

For my accounting spreadsheet for example I have single cell formulae that are hundreds of characters long which can be a PITA to tweak when the need arises!

 

[HandySparks]

Sorry no

If that's a reply to this:
Unless I'm misreading BGB 543.1.3, don't you take the square root of I²t before dividing by k, not after?

How do others here interpret the formula in the BGB?

 

[D Skelton]

If that's a reply to this:
Unless I'm misreading BGB 543.1.3, don't you take the square root of I²t before dividing by k, not after?

How do others here interpret the formula in the BGB?

S is equal to... the square root of I²t... Which is then divided by k.

In other words, the square root of I²t is divided by k to get S.

k does not form part of the equation which is square rooted.