Calculating expected current in a 3-phase delta circuit 3

[PaulKraemer]

Hi,

I have three electric heaters with resistance 82.3 ohms each, wired in a delta configuration as shown on the left below. As I see it, each 480 VAC line-to-line voltage is applied across a parallel circuit as shown on the right below.

I calculate the total resistance of the circuit on the right as 54.87 ohms. The formula I = E/R = 480/54.87 = 8.75 amps leads me to believe that my expected current draw on each line would be 8.75 amps, but I am not entirely confident about this.

I am not sure if the delta-configuration introduces any complexity that would make my simple calculation invalid.

If anyone can tell me if my calculation is correction and if not, how/where I went wrong, I would greatly appreciate it.

Thanks in advance,
Paul

 

[itsmoked]

Ouch again. LOL

Keith Cress
kcress -

http://www.flaminsystems.com

 

[waross]

I had it right.
I was going to use an example of an estimate of pi as well, and then decided to edit it out before posting.
I screwed up the edit and took out the wrong value.
I had a reason, but not an excuse.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[davidbeach]

Conservation of energy. Each resistor draws 2.8KW. There are three of them. The circuit needs to supply 8.4kW. 8.4kW at 480V is 10.1A. An awful lot of work in the preceding posts to get to a very simple answer.

 

[che12345]

Dear Mr. PaulKraemer,
My sincere apology. There was a mistake, as correctly pointed out by learned Mr.sushilksk.
Mr. sushilksk
Thank you for pointed out the error.
It should be IA = (i12 - i31)
The value is correct IA = 10.101 A
Che Kuan Yau (Singapore)

 

[davidbeach]

Still, why vector math for a problem that can be solved by adding Watts to Watts?

Vector math is a wondrous thing, but swatting flys with sledge hammers is still swatting flys with a sledge hammer no matter how nicely you dress it up.

 

[crshears]

But just think of all the exercise you get!!!

CR

"As iron sharpens iron, so one person sharpens another." [Proverbs 27:17, NIV]

 

[waross]

And the opportunity for extra mistakes and trypos, typros, tiepoes, ah sh** you know what I mean.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[crshears]

Yeah, I no what you mien.

CR

"As iron sharpens iron, so one person sharpens another." [Proverbs 27:17, NIV]