Electrical & Controls
Heater element power (star / delta)
Heater bank power and current from element resistance, or the resistance you should measure.
Calculating…
How it's calculated
Star: element voltage = V ÷ √3
Delta: element voltage = V
Element power = V_element² ÷ R
Measuring element resistance (isolated and disconnected) is the quickest way to find a failed heater element. An open element reads infinite resistance; a shorted or earth-faulted element needs an insulation test as well.
The same element gives three times the power in delta as in star. Element resistance rises when hot, so cold readings give slightly more power than actual.