Permited voltage drop for a 240 volt circuit is 7.2 volts.
in this case the design perameters call for a 1.5% drop or less.
can anyone point to something in writing that could help to argue my case?
240v 1ph circuit 16.7amps
using 8awg I get a drop of 2.5v
Is that 2% based on 120v from each conductor to ground, or 1% of 240v.
It will be based on the voltage on the load and/or net load. If the 16.7 amps made up of a bunch of 120 volt loads, you will need to do a 120 volt calc for the worst unbalanced case.When somebody needs that in terms of % drop, do I use 240v, or 120v?
I understand that 2% of 240 is the same as 1% of 120.
When I run calculations I get a 2.5v drop. When somebody needs that in terms of % drop, do I use 240v, or 120v?
It is a 120/240v circuit.
Not to be the CODE police but voltage drop is a recommendation per 210.19(1) ex. 2 FPN per 90.5(C).
Permited voltage drop for a 240 volt circuit is 7.2 volts.
Has to be exactly 5 volts? That is tough. :grin:...anytime I call and report over or under of 5 volts or more
You should because that will determine the current value and which impedance it flows though.you obviously don?t know what's the nominal is, since the load can be connected as 120 or 240 using the same wire. So, in that case you better do not use % term with reference to that drop.
... but I've got an engineer sizing wire based on the voltage for the individual conductor.
in this case the design perameters call for a 1.5% drop or less.