Calculations, Delta Heater Circuit

[dasarmin]

I?ve seen in a spreadsheet form, a tool that will calculate among other things ?Current?& ?Resistance? of a Delta 3-Phase Heater Circuit. At our facility most of our heater circuits are 480Vac 3PH Resistive type. Ideally, we try to balance the load by installing similar wattage heaters across each phase, making calculation of the current straight forward (I = P / (1.73*480)). For instance 3 x 1500Watt heaters in a delta 480 circuit: I = (4500 / (480*1.73)) = 5.42Amps in each leg Ia, Ib & Ic. The calculation gets more complicated as the wattage between phases or the numbers of heaters vary.
Also in a similar spreadsheet form, if you don?t know wattages but can measure the phase to phase resistance, this information can inserted into the spreadsheet and phase currents can be calculated.
If anyone can provide or has seen such a tool on web, I?d appreciate it.

 

[iceworm]

I?ve seen in a spreadsheet form, a tool that will calculate among other things ?Current?& ?Resistance? of a Delta 3-Phase Heater Circuit. ... The calculation gets more complicated as the wattage between phases or the numbers of heaters vary. ...
... If anyone can provide or has seen such a tool on web, I?d appreciate it.

das -
This is three equations, three unknowns. Just guessing: I'd suggest start assuming Wye connected heaters. Solve for the resistances. Do a Y - D transformation to get the delta resistances I'd think the equations would fall right into a spreadsheet. Just have to not have any calcs that assume the neutral is 0 Volts

I suspect I am missing something.

ice

 

[kwired]

Like Ice said these are simple calculations.

If you know how to make spreadsheets this would be a pretty simple one.

If you don't know how or don't want to learn how to make spreadsheets you probably know someone that does. Give them the formulas for the calculations and bribe them into making you one.

 

[iceworm]

Like Ice said these are simple calculations. ...

The currents are a bit more complex (that would be a pun) :blink:

However, since the loads are all resistive. the phase angles are known. So it shouldn't be too bad.

again, unless there is something I am missing

ice