AutomationDirect DURAPULSE Series User Manual page 116

Chapter 4: AC Drive Parameters
Example 2: Standard Operation with Increased Maximum Output Frequency
This example illustrates how to run the motor faster than its base speed. For this
purpose, the only required parameter change is P0.04, Motor Maximum RPM.
(Motors produce reduced output torque when running above their base speed.)
W
ARNING
maximum speed rating for the motor you are using. If this information is not readily
available, consult your motor manufacturer.
The analog input adjustment parameters P4.01 through P4.04 can remain
defaulted, as determined by the analog input calculations shown below. The
increased Maximum Output Frequency can be obtained regardless of whether the
Source of Frequency Command is an analog input or one of the other sources,
such as the keypad, RS-485 communication interface, jog, or multi-speed settings.
• Minimum Frequency Reference = 0Hz
• Maximum Frequency Reference = 70 Hz
• Motor Maximum RPM = 2042 rpm
Calculations
A) Max Output Frequency = (2042 rpm / 1750 rpm) x 60 Hz = 70 Hz
B) Analog Offset % = (0Hz / 70 Hz) x 100 = 0%
C) Analog Gain % = ((70 Hz – 0Hz) / 70 Hz) x 100 = 100%
D) Mid-point Frequency = ((70 Hz – 0Hz) / 2) + 0Hz = 35 Hz
Parameter Settings
P0.04: 2042 – Motor Maximum RPM
P4.01: 00 (default) – Offset disabled
P4.02: 00 (default) – 0% Analog Input Offset
P4.03: 100 (default) – 100% Analog Input Gain
P4.04: 00 (default) – Forward Motion Only
Results
Max. Output Frequency
Motor Base Frequency
Mid-Point Frequency
4–48 DURA
PULSE
: The Motor Maximum RPM parameter (P0.04) should never exceed the
70Hz
60Hz
35Hz
0Hz
0V
-10V
0mA
4mA
AC Drive User Manual
5V 10V
0V 10V
10mA 20mA
12mA 20mA
1st Ed. Rev. D 05/2013