why is volt drop important???

[bobbybrown]

whats the reason we worry about volt drop?
It cant be because of the design of fittings etc.. because the actual voltage can be 230v +10% -6% percent,
i believe if there is a voltdrop then the current will increase as per ohms law
maybe its something to do with potential differences e.g 230 at one end and 236.9 at the other (3%) however i dont understand why would that cause concern????

 

[pushrod]

just another quick question regrading volt drop, the 3 percent rule on lighting, is that 3 percent on the actual measured voltage or 3 percent on 230v?

imo it would make sense to be based on 230v and not measured voltage . e.g if your supply was 1 percent over 230v then you should be allowed up to 4 percent volt drop

i know the further you are away from the substation the lower your measured voltage will be, out of interest does it drop much or will it still be nearly at 230v?

the 3% figure is on 230 V as that is what you should expect even though reality is that it will often be more. So for lighting you calculate for Vd to not exceed 6.9volts

edit: in my experience supply voltage has always exceeded 230V