calculating design current in a ring circuit

[dave30]

hello and thanks again for all your answers got another question for yous


ok im trying to calculate design current for a ring

if it was a shower unit say 7.5kw at 230 volts i would do 7500 / 230 = 32.6 amp this i no how to do

cant think how you would do it for ring or even if you can do it

could some one please help its a 32 amp ring on a 230 volt supply

 

[marc_v33]

youve answered your own question 32a is your design current..

16a per leg of the ring

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[Ben Butcher]

Hello, the design current of the circuit is the maximum draw in the case of a ring i.e the breaker rating. If this is a cable calc there are of course many other aspects, insulation, grouping, etc. Hope that is of some help. Same for a lighting circuit or radial socket circuit etc.

 

[i=p/u]

/4 for vd.

 

[plugsandsparks]

Bit more complicated with a ring to determine how a load will distribute current across both legs, easiest way would be to measure continuity from your load point to the breaker on each leg, in theory the proportions of current going down each leg is inversely proportional to the resistance.