Hubbell ETXA Series, Description, Installation And Operation Manual, Page: 8 / 52

8
Formulas:
Wattage De-rating Formula:
Applied Voltage
2
Rated Voltage
2
× Rated Wattage = Actual Wattage
For example: If installing a 27 kW unit when actual voltage is 212 V,
212
2
=
44,944
= 0.78 × 27,000 W = 21,060 W @ 212 V
240
2
57,600
Amperage Formula:
Watts
= Amps (Single Phase)
Watts
÷1.73 = Amps (3-Phase)
Volts Volts
Flow Rate Formulas:
To determine power (kW) requirement
GPM ×°F

T × 0.1465 =kW
To determine temperature rise
kW × 6.824 ÷GPM =°F

T
To determine flow rate
kW × 6.824 ÷°F

T =GPM