Length of flex

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Nine Elms
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Length of flex

#1

Post by Nine Elms »

Evening All

I am in the process of wiring up a bus wire and droppers. Are there recommended lengths for the dropper flex? The way I am proposing the bus wire layout would mean some of the flex lengths would be longer than others, would this be a problem?

John
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Walkingthedog
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Re: Length of flex

#2

Post by Walkingthedog »

Are you taling about several feet or a few inches. In my view it won’t make any difference.
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Nine Elms
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Re: Length of flex

#3

Post by Nine Elms »

Thank you WTD.

My planned layout may require droppers of no more than 1/2 metre, so it looks okay!!

John
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Brian
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Re: Length of flex

#4

Post by Brian »

A lot depends on the number of droppers and their wire size!
So, if every piece of track has a dropper pair then you can use 7/0.2mm wire, but try and keep its length to around no more than 300mm (12 Inches).
Where droppers are not frequently installed/spaced then use 16/0.2mm and ideally to no more than 500mm in overall length maximum Bus wire to rail. :D
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nigelwright7557
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Re: Length of flex

#5

Post by nigelwright7557 »

A piece of wire is just a piece of wire ?
Actually, no.

I did some research for an electronic project which required some long runs of wire.
So I bought in various cables to test.
I was quite shocked at just how much the different wires varied in resistance per metre.
So for a long run you can get quite a voltage drop with poor wire.

Clearly thickness of wire makes a difference too as it affects resistance per metre length.
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Walkingthedog
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Re: Length of flex

#6

Post by Walkingthedog »

The clue is the thickness of wire used in a house power supply. Probably why they don’t use lighting flex on the national grid pylons :D
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