Current reading

hillbilly1

Senior Member
Location
North Georgia mountains
Occupation
Owner/electrical contractor
I was consulted on a job where one of the six parallel feeders underground had melted. They wanted to pipe the replacement overhead. They weren’t too happy when I told them that the entire feed had to go overhead, not just the one, LOL!
 

GoldDigger

Moderator
Staff member
Location
Placerville, CA, USA
Occupation
Retired PV System Designer
I was consulted on a job where one of the six parallel feeders underground had melted. They wanted to pipe the replacement overhead. They weren’t too happy when I told them that the entire feed had to go overhead, not just the one, LOL!
But if you have a three phase feeder, you could run all the wires of the parallel set for one phase via a different route than the other phases. (As long as you take care of things like unbalanced current through the wall of a ferrous metal enclosure and any other rules that prohibit a uniphase wire routing in this circumstance.)
 

ptonsparky

Senior Member
Location
NE (9.06 miles @5.9 Degrees from Winged Horses)
Occupation
Electrical Contractor
But if you have a three phase feeder, you could run all the wires of the parallel set for one phase via a different route than the other phases. (As long as you take care of things like unbalanced current through the wall of a ferrous metal enclosure and any other rules that prohibit a uniphase wire routing in this circumstance.)
Would this increase the impedance of the feeders?
Miligaus?
Does this mean the phases can be different conductor type or even sizes as long as they are sufficient for the load and are protected properly.
Three Cu phase A
Four Al phase B
Two Cu phase C
Four Al Neutral

Now add distance between phases does not matter?
 

kwired

Electron manager
Location
NE Nebraska
Would this increase the impedance of the feeders?
Miligaus?
Does this mean the phases can be different conductor type or even sizes as long as they are sufficient for the load and are protected properly.
Three Cu phase A
Four Al phase B
Two Cu phase C
Four Al Neutral

Now add distance between phases does not matter?
I think how much depends on surrounding conditions.

Will increase potential EMF's in the vicinity as well.
 
Top