Reg 612.14 - BS7671:2008 States:
Where required to verify compliance with Section 525 the voltage drop may be evaluated by:
i) measuring the circuit impedance
ii) using calculations using cable length v load current for different cable sizes.
Now..
Issue 1 - The regulation does not mention "by measurement". Why not?
Issue 2 - Regarding option i), what do you assume this is referring to?
Does it mean use the sum of R1 and Rn and multiply that by the design current? (for parallel v.d)
Does it mean use R1 and multiply it by the design current (for series v.d)
Does it mean that as long as Zs is verified we assume the voltage drop is acceptable? (which doesn't seem likely having just done a random calc using a design current and the Max Zs for a device). This clearly includes the Ze though.
Does it mean something else?
Issue 3 - If i) does require a calculation why does it not state it?
Where required to verify compliance with Section 525 the voltage drop may be evaluated by:
i) measuring the circuit impedance
ii) using calculations using cable length v load current for different cable sizes.
Now..
Issue 1 - The regulation does not mention "by measurement". Why not?
Issue 2 - Regarding option i), what do you assume this is referring to?
Does it mean use the sum of R1 and Rn and multiply that by the design current? (for parallel v.d)
Does it mean use R1 and multiply it by the design current (for series v.d)
Does it mean that as long as Zs is verified we assume the voltage drop is acceptable? (which doesn't seem likely having just done a random calc using a design current and the Max Zs for a device). This clearly includes the Ze though.
Does it mean something else?
Issue 3 - If i) does require a calculation why does it not state it?