Basic Volts/Hertz For Fan/Pump Applications - Allen-Bradley Kinetix 5700 User Manual

Appendix E Motor Control Feature Support
408

Basic Volts/Hertz for Fan/Pump Applications

The Basic Volts/Hertz Fan/Pump (fan/pump) method is based on the Basic
Volts/Hertz (V/Hz) method, but is specifically tailored for fan/pump
applications.
Figure 210 - Output Voltage Equation
2
f
x
=
V V – V
x n boost
f
n
For maximum system efficiency, fan/pump loads use variable frequency drives
that are equipped with a specific V/Hz curve where voltage is proportional to
square of the frequency.
Figure 211 - Basic Volts/Hertz Fan/Pump Method
Voltage, max
Base Voltage
(nameplate)
Run Boost
TIP The Fan/Pump control method supports the run-boost attribute, but does
not support break-voltage, break-frequency, or start-boost.
Rockwell Automation Publication 2198-UM002G-EN-P - February 2019
Where:
V = Output voltage
x
+ V
boost
f = Output frequency
x
V = Rated voltage
n
F = Rated frequency
n
V = Run boost voltage
boost
Frequency (Hz) Base Frequency,
(nameplate)
Frequency,
max