618electrician
Member
- Location
- St. Louis
- Occupation
- Maintenance electrician
208 a phase A 10 amps phase B 5 amps neutral amps = ??????????????????????????????????????????????????????????????????????????????????????
208 three phase
- Thread starter 618electrician
- Start date
Eddie702
Licensed Electrician
- Location
- Western Massachusetts
- Occupation
- Electrician
If it is single phase 2 hots and a neutral Phase A 10 amps phase B 5 amps the neutral carries the imbalance which is 10-5=5 amps.
Not for a wye system
Eddie702
Licensed Electrician
- Location
- Western Massachusetts
- Occupation
- Electrician
He only gave amps for phase a and phase b. I don't see phase c being used. 2 hots and a neutral. For that portion of the circuit only will the neutral not see a 5 amp load?
618electrician
Member
- Location
- St. Louis
- Occupation
- Maintenance electrician
THREE PHASE
Eddie702
Licensed Electrician
- Location
- Western Massachusetts
- Occupation
- Electrician
You don't have to yell. What is the load on phase C if they are using 3 phase. The post title says three phase but he is only using 2 legs and a neutral.
hillbilly1
Senior Member
- Location
- North Georgia mountains
- Occupation
- Owner/electrical contractor
If it is a three phase circuit, then it’s unsolvable without knowing what C phase current is.
Additionally you would need to know the phase of the currents/power factors of the loads.
- Location
- New Jersey
- Occupation
- Journeyman Electrician (retired)
0 load on C phase I get 8.7 amps on the neutral.
Same here, assuming the currents are 120° from each other.
In a wye configuration they are
For a fun read see the thread from long ago and use two of the phases
Unbalance neutral current in a 3 phase system
I have been told that to calculate the amount of current on the neutral of a three phase system, you simply take the square root of the highest phase current. I have an extensive engineering backgrond and I know that this is not possible. For example, if phase A = 49A and phase B = 47A and phase...
forums.mikeholt.com
If you have loads with various power factors, they may not be.
Tulsa Electrician
Senior Member
- Location
- Tulsa
- Occupation
- Electrician
hillbilly1
Senior Member
- Location
- North Georgia mountains
- Occupation
- Owner/electrical contractor
Three phase source, single phase load?
You are mathematically correct but if the service is built with metal conduit and you check it at the panel you will always read lower as much as 30% !